[top]
000
FXUS62 KMFL 200142
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
942 PM EDT FRI SEP 19 2008
.UPDATE...
REMNANTS OF AFTERNOON/EARLY EVENING CONVECTION HAVE SHIFTED TO THE
GULF WATERS OFF THE SOUTHWEST COAST...AS IS TYPICALLY THE CASE
IN AN ESTABLISHED NORTHEAST FLOW REGIME SUCH AS THE ONE CURRENTLY
IN PLACE OVER THE REGION. HAVE ADJUSTED EVENING POP GRIDS TO
REFLECT HIGHER RAIN CHANCES EARLY OVER THE GULF WATERS...WITH
SCATTERED ACTIVITY EXPECTED TO CONTINUE THROUGHOUT THE NIGHT OVER
THE LOCAL ATLANTIC WATERS. OTHERWISE...MADE MINOR ADJUSTMENTS TO
WIND AND CLOUD COVER GRIDS...BUT TEMPERATURES/DEW POINTS LOOK TO
BE ON TRACK AT THIS TIME. UPDATED PRODUCTS WILL BE ISSUED SHORTLY.
70/DD
&&
.AVIATION DISCUSSION... /ISSUED 729 PM EDT FRI SEP 19 2008/
AVIATION...DOPPLER RADAR SHOWING SCT-NMRS SHWRS OVER ATLC WATERS
MOVING SOUTHWEST. WL EXPECT A FEW OF THESE TO PASS CLOSE TO ERN
TERMINALS CLOSEST TO THE COAST THROUGH 06Z BUT DISSIPATING BEFORE
REACHING KTMB. SFC WINDS SHOULD GRADUALLY DECREASE TO 5-10 KTS BY
06Z. VFR CONDITIONS SHOULD REMAIN OVR KAPF THROUGH THE ENTIRE
FORECAST PERIOD. SFC WINDS SHOULD BE MORE EASTERLIES AND NOT AS
GUSTY OVER ERN TERMINALS SATURDAY, HOWEVER, EXPECT SHOWER ACTIVITY
CURRENTLY OVER ATLC WATERS/NRN BAHAMAS TO BE ADVECTED WESTWARD AND
SO WILL INDICATE VCSH AGAIN IN THE TAFS FOR SAT MORNING. GUIDANCE
SUGGEST TSTM ACTIVITY OVER ERN AREAS EARLY SATURDAY AFTERNOON, SO
WL INDICATE VCTS FOR ALL ERN TERMINALS STARTING AT 17Z BUT EXPECT
SEA BREEZE WL PUSH ALL ACTIVITY INLAND AWAY FROM THE TERMINALS
(EXCEPT KTMB) BY 20Z.
.PREV DISCUSSION... /ISSUED 314 PM EDT FRI SEP 19 2008/
DISCUSSION...THIS MORNINGS RAOB COMBINED WITH THE CURRENT MIMIC-
TPW IMAGES SHOW DRIER AIR STILL MOVING SOUTH TOWARDS EXTREME
SOUTH FLORIDA. 88-D SHOWS ISOLATED TO WIDELY SCATTERED SHOWERS
MOVING SOUTHWEST. HAD TO CHANGES THE POPS FOR THE REST OF TODAY
FROM 40 PERCENT TO AT MOST 20 PERCENT. IN THE SHORT TERM, THE
GFS40 WANTS TO MOVE A TROUGH AND ASSOCIATED MOISTURE WEST FROM THE
CENTRAL BAHAMAS BY SAT AND SAT NGT BUT THE NAM12 SHOWS A VERY SLOW
MOVEMENT WESTWARD. HAVE SPLIT THE DIFFERENCE THROUGH SUNDAY AND
WENT LOW CHC POPS. THE NAM12 FINALLY SHOWS THE MOISTURE AND TROUGH
REACHING SOUTH FLORIDA BY MONDAY. I INHERITED GOOD POPS WITH AN
INCREASE BY MON SO THIS LOOKS GOOD. GFS40 MEAN RH RISES BY TUE AND
WENT CLOSE TO MEXMOS WITH A HIGHER END CHANCE CATEGORY.
ALSO IN THE SHORT TERM, A MID LEVEL TROUGH DEEPENS OVER THE
WEEKEND AND DEVELOPS A LOW OFF THE CAROLINA COAST BY FRIDAY BUT
AS THE MID LEVEL LOW MOVES NORTH AND WEAKENS, THE ATLANTIC LOW
MOVES NORTH A WEAKENS ALSO. IN THE MEANTIME, A DECENT NORTHEAST
FLOW EXISTS OVER THE SOUTHEAST UNITED STATES UNTIL THE LOW WEAKENS
SUN NGT. THIS WILL SEND SOME SWELLS SOUTHWARD INTO FLORIDA. AN
EVEN STRONGER NE FLOW DEVELOPS MID WEEK TO THE WEST OF AN INVERTED
TROUGH.
MARINE...WINDS WILL BE NE-E 5 TO 10 KNOTS WITH SEAS 2 TO 4 FEET
THROUGH SUN NGT EXCEPT TO 4 FEET PALM BEACH WATERS SAT NGT DUE
TO 3 FOOT SWELLS. WAVES AND SWELLS DECREASE BY MONDAY OVER THE
ATLANTIC TO LESS THAN 4 FEET. WINDS WILL BE A BIT STRONGER OVER
THE GULF OF MEXICO THROUGH SAT AND ON WED.
FIRE WEATHER...NO CONCERNS HERE AS THE RH`S WILL BE ABOVE CRITICAL
VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 89 77 89 / 20 30 30 40
FORT LAUDERDALE 78 90 79 89 / 20 30 30 30
MIAMI 77 90 78 90 / 20 30 30 30
NAPLES 74 91 74 90 / 20 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...70/DD
SHORT TERM/AVIATION...47/RHG
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000
FXUS62 KKEY 200114
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
915 PM EDT FRI SEP 19 2008
.DISCUSSION...
.CURRENTLY...
KBYX DETECTS WIDELY SEPARATED SHOWERS AND THUNDERSTORMS THROUGHOUT
THE FORECAST AREA. SKIES OVER THE ISLAND CHAIN ARE VARIABLY CLOUDY.
WINDS OVER LAND ARE EAST AT 10 TO 15 MPH. C-MAN WINDS...ON
AVERAGE...ARE EAST TO SOUTHEAST NEAR 15 KNOTS...WITH GUSTS NEAR 20
KNOTS. TEMPERATURES ARE IN THE LOWER 80S. ONLY ABOUT THREE DEGREES
OF COOLING IS EXPECTED OVERNIGHT DUE TO GENTLE TO MODERATE EAST
SURFACE WINDS OVER WATER WITH TEMPERATURES IN THE MID 80S.
.SHORT TERM (OVERNIGHT)...
IN THE LOW TO MID LEVELS OF THE ATMOSPHERE...A TROPICAL WAVE IS
LOCATED ALONG 75W SOUTH OF 19N. THIS TROPICAL WAVE WILL MOVE TO THE
WEST AT 10 TO 15 KNOTS OVERNIGHT. THE NORTHERN EXTENT OF THIS
TROPICAL WAVE WILL REMAIN SOUTH OF CUBA TONIGHT INTO THIS WEEKEND...
RESULTING IN NO IMPACT TO THE LOCAL WEATHER. IN THE UPPER LEVELS OF
THE ATMOSPHERE...A TROUGH OF LOW PRESSURE WILL BE LOCATED OVER THE
BAHAMAS TONIGHT. THE 00Z KKEY SOUNDING IS MODERATELY UNSTABLE AND
TYPICALLY MOIST FOR MID SEPTEMBER...WITH A PRECIPITABLE WATER (PWAT)
VALUE JUST ABOVE ONE AND THREE QUARTERS OF AN INCH. ATMOSPHERIC
MOISTURE WILL DECREASE OVERNIGHT. BY SUNRISE SATURDAY...PWAT VALUES
SHOULD BE JUST BELOW ONE AND THREE QUARTERS OF AN INCH...WHICH IS
NEAR THE 25TH PERCENTILE FOR THIS TIME OF YEAR. ATMOSPHERIC DRYING
TONIGHT SHOULD LIMIT POPS TO SLIGHT CHANCE CATEGORY. THE ZONE
FORECASTS FOR THE FLORIDA KEYS WILL BE UPDATED SHORTLY TO DECREASE
RAIN CHANCES FOR TONIGHT.
&&
.MARINE...
MODERATE EAST SURFACE WINDS WILL PREVAIL ON ALL KEYS WATERS
OVERNIGHT. NO ADVISORIES OR CAUTIONARY STATEMENTS EXPECTED TONIGHT
THROUGH AT LEAST WEDNESDAY.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL AT THE KEYW AND KMTH ISLAND TERMINALS.
ISOLATED SHOWERS AND THUNDERSTORMS WILL IMPACT THE ISLANDS. SURFACE
WINDS WILL BE BETWEEN 10 AND 12 KNOTS FROM ABOUT 060 DEGREES...GUSTS
UP TO 20 KNOTS. WINDS WILL GRADUALLY DECREASE LATE...AS THE PRESSURE
GRADIENT RELAXES. BRIEF MVFR/IFR CIGS AND/OR VIS WILL BE LIKELY
WITHIN ANY SHOWERS AND STORMS THAT IMPACT THE TERMINALS.
&&
.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...IN 1890...THE LOW TEMPERATURE
IN KEY WEST WAS 70 DEGREES. THIS SET THE DAILY RECORD FOR MINIMUM
TEMPERATURE MEASURED IN KEY WEST ON SEPTEMBER 19TH...A RECORD WHICH
STILL STANDS 118 YEARS LATER.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE/FIRE/CLIMATE/DIGITAL...BS
AVIATION/NOWCASTS....................FUTTERMAN
DATA ACQUISITION.....................DR
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
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000
FXUS62 KTBW 200052
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
852 PM EDT FRI SEP 19 2008
DRY AND QUIET AFTERNOON AND EVENING AS WV SHOWING UPPER TROF DOWN
FROM THE MID ATLANTIC TO OVER FL AND W ATLANTIC. 00Z SOUNDING
VERY DRY AS WELL WITH PWATS DOWN TO 1.26 INCHES WITH SUBSIDENCE
ALOFT. SFC HIGH PRESSURE DOWN THE EASTERN SEA BOARD BRING DRY LL
AIRMASS AND DEW POINTS IN THE MID TO UPPER 60S TO THE FL PENINSULA
THIS EVENING. WITH DRY AIRMASS AND CLEARING SKIES TEMPS TO FALL A
FEW DEGREES BELOW NORMAL FOR PLEASANT OVERNIGHT. LATEST GRIDS AND
FCSTS ON TRACK.
&&
.MARINE...3-4 MB GRADIENT COMBINED WITH EASTERLY SURGE THIS EVENING
PRODUCING MODERATE WINDS OF AROUND 15 KTS OVER THE E GULF. GRADIENT
BEGINS TO WEAKEN OVERNIGHT INTO SAT WITH WINDS WEAKENING AS WELL.
&&
.AVIATION...VFR CONDITIONS TO CONTINUE.
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
RD
[top]
000
FXUS62 KJAX 200043
AFDJAX
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE JACKSONVILLE FL
842 PM EDT FRI SEP 19 2008
.UPDATE...00Z SOUNDINGS SHOW LLVL MOIST/UNSTABLE AIRMASS ACRS KJAX
RAOB SITE WITH MORE STABLE CONDITIONS AT KCHS/KMLB/KTAE. BASED ON
SOUNDINGS AND RADAR TRENDS...WILL INCREASE POPS TO LIKELY ALONG
COAST OF FAR SE GA/NE FL...40-50 FURTHER INLAND OVER 2 ROWS OF
COUNTIES FROM COAST...AND JUST 20 POPS IN THE WRN HALF OF OUR CWA.
NAM SUGGESTS WDSPRD RAIN MOVES WELL INLAND LATE TNGT...NOT READY
TO BITE ON THAT SOLUTION BUT 00Z SOUNDING DOES SUGGEST GREATER
COVERAGE THAN IN PRIOR FORECAST. NO OTHER CHGS PLANNED IN UPDATE.
WSR-88D HAS BEEN DETECTING OCNL ROTATION WITH CELLS OFF NE FL COAST.
POTENTIAL FOR WATERSPOUTS WITH BAND OF CELLS APPROACHING COAST...
SWA ISSUED TO INDICATE THIS POTENTIAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 83 62 85 / 20 10 0 30
SSI 68 80 69 82 / 60 30 20 30
JAX 68 82 68 84 / 50 30 20 40
SGJ 71 82 71 83 / 50 40 30 60
GNV 64 85 65 87 / 20 30 10 50
OCF 66 86 67 87 / 20 30 10 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH TO ST
AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH FL OUT
20 NM.
&&
$$
WOLF/PETERSON/KEEGAN
[top]
000
FXUS62 KMLB 200031
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
830 PM EDT FRI SEP 19 2008
.DISCUSSION...
...NE SWELLS AND INCREASING THREAT FOR RIP CURRENTS EXPECTED AT THE
BEACHES THIS WEEKEND...
CURRENTLY-TONIGHT...DRY AIR ALOFT ON THE BACKSIDE OF MID/UPPER
TROUGH STILL COVERS THE AREA. THIS HAS KEPT ATLANTIC SHOWERS RATHER
ISOLATED. BROAD INVERTED TROUGH WELL OFFSHORE IS KEEPING THE LOW
LEVEL FLOW BACKED TO THE NORTHEAST WITH LAND BASED STATIONS
REPORTING MOSTLY A NORTH FLOW. THIS WILL KEEP SHOWERS CHANCES LOW
AND CONFINED TO NEAR THE COAST.
WILL REMOVE POPS FOR THE INTERIOR AND LEAVE A 20 PERCENT CHANCE
ALONG THE COAST.
&&
.AVIATION...MAINLY VFR EXCEPT FOR BRIEF MVFR NEAR THE COAST
ASSOCIATED WITH ISOLATED SHOWERS.
&&
.MARINE...GRADIENT APPEARS TO BE WEAKENING AND SEAS ARE BELOW 5 FEET
SO WE WILL NOT NEED AN EXERCISE CAUTION STATEMENT. WE MAY NEED TO
TWEAK THE CURRENT FORECAST WINDS DOWN FOR THE WEEKEND AS IT WOULD
SEEM THAT THIS TREND WILL CONTINUE. A NORTHEAST SWELL WILL KEEP SEA
HEIGHTS FROM CHANGING MUCH BUT THE WIND WAVE COMPONENT SHOULD BE
SMALLER. THE LATEST GFS SHOWS DEEPER MOISTURE ON SUNDAY SO THERE
SHOULD BE AN INCREASE IN RAIN CHANCES BY THEN.
&&
.HYDROLOGY (PREVIOUS DISCUSSION)...SLOW FALL TO CONTINUE OVER THE
MIDDLE ST JOHNS RIVER BASIN THRU EARLY NEXT WEEK...ALTHOUGH ALL
FORECAST POINTS WILL CONTINUE ABOVE FLOOD STAGE. FOR THE LATEST INFO
ON ST JOHNS RIVER LEVEL SEE THE RIVER FLOOD STATEMENT /MIAFLSMLB/.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
LASCODY/WEITLICH
[top]
000
FXUS62 KTAE 200029
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
830 PM EDT FRI SEP 19 2008
.DISCUSSION...HIGH PRESSURE CENTERED OVER NOVA SCOTIA CONTINUES TO
RIDGE DOWN THE ERN SEABOARD INTO N FL...BRINGING US OUR FIRST TRULY
LOW HUMIDITY DAY OF THE SEASON. AN INVERTED TROUGH WAS ANALYZED IN
THE CENTRAL GULF WITH A THETA-E RIDGE EXTENDING NWD FROM THAT INTO
ERN MS. SHOWERS AND STORMS TODAY WERE LIMITED TO THESE AREAS AS WELL
AS IN AN AREA OF CONVERGENT ONSHORE FLOW OFF THE ATLANTIC INTO NE FL
AND SE GA. WATER VAPOR IMAGERY INDICATES THAT THE MAIN ARES OF
SUBSIDENCE AND DRY AIR HAS PUSHED E OF THE FORECAST AREA AS A SHORT
WAVE TROUGH PUSHES IN FROM THE W. SOME MID AND HIGH CLOUDS HAVE
ATTENDED THIS TROUGH, BUT THESE HAVE BEEN HAVING A HARD TIME MAKING
SIGNIFICANT EWD PROGRESS. WE DO SEE SOME LOWER CLOUDS HEADING WWD
TOWARD S CENTRAL GA THE THE ERN FL BIG BEND. HOWEVER, THE SHOWER
ACTIVITY SHOULD STAY E OF THE AREA. TEMPS ARE FORECAST TO ONCE AGAIN
DIP DOWN INTO THE 60S ACROSS MOST AREAS. THE ENCROACHING CLOUD COVER
MAY KEEP TEMPS FROM GETTING AS LOW AS THE GUIDANCE SUGGESTS. WILL
MONITOR FOR ANOTHER HOUR OR TWO BEFORE MAKING ANY ADJUSTMENTS TO
TONIGHT`S MINS. LOOKING AHEAD TO SAT...IT LOOKS LIKE A GREAT DAY FOR
FOOTBALL HERE IN TALLAHASSEE WITH JUST SLIGHTLY HIGHER DEW POINTS
AND A NEGLIGIBLE POP.
&&
.MARINE...A HIGH PRESSURE RIDGE WILL REMAIN ANCHORED TO THE NE OF
THE WATERS THROUGH THE WEEKEND WHICH, WILL MAINTAIN THE MODERATE E
TO NORTHEAST WIND FLOW. WINDS AND SEAS WILL INCREASE TO EXERCISE
CAUTION CRITERIA AT TIMES, DURING THE LATE NIGHT AND EARLY
MORNING HOURS THROUGH SATURDAY NIGHT. WE PLAN TO EXPAND THE CAUTION
HEADLINE TO THE REMAINING LEGS AS ALL BUT IMMEDIATE COASTAL AREAS
WILL EASILY SEE 15-20 KT OVERNIGHT. THE GRADIENT DOES NOT APPEAR TO
BE QUITE AS TIGHT AS LAST NIGHT WHEN A BRIEF SCA EVENT OCCURRED.
&&
.AVIATION...VFR CONDITIONS ONGOING ACROSS THE REGION THIS EVENING. A
MID LEVEL CLOUD DECK IS SPREADING EAST AS IT THINS OUT. THE MAV
GUIDANCE FAVORS MVFR...AND EVEN SOME IFR...CIGS AT ALMOST ALL OF THE
TERMINALS TONIGHT. INCREASING MOISTURE FROM THE EAST IS LOOKING LIKE
IT WILL GET INTO OUR EASTERN TERMINALS AFTER MIDNIGHT...BUT WITH THE
WINDS REMAINING UP...RESTRICTIONS WILL LIKELY BE CIGS INSTEAD OF
VSBYS. THE SREF GUIDANCE DOES NOT SUPPORT MUCH IN THE WAY OF
RESTRICTIONS OVERNIGHT...SO WILL USE A BLEND OF THESE TWO SOLUTIONS
AND SETTLE ON MVFR TEMPOS ALL SITES EXCEPT PFN AROUND DAYBREAK. VFR
CONDITIONS ARE EXPECTED AFTER 14Z AT ALL TERMINALS.
&&
.FIRE WEATHER...A VERY DRY AFTERNOON SAW THE RH DROP BRIEFLY TO
AROUND 35 PERCENT ACROSS INLAND N FL, BUT DURATIONS WERE
INSUFFICIENT TO MEET THE STATE OF FL RED FLAG CRITERIA. WE ALSO
NOTED 3-4 HOURS OF RH AROUND 25 PERCENT UP AT ABY AND SURROUNDING
AREAS IN GA, ENOUGH TO MEET THE GA COOL SEASON RED FLAG CRITERIA
(NOV 1-APR 30)...BUT NOT THE WARM SEASON CRITERIA. THIS SHOULD BE
THE DRIEST DAY OF THIS STRETCH AS MOISTURE LEVELS GRADUALLY INCREASE
OVER THE WEEKEND.
&&
.PREV DISCUSSION...
200 PM EDT FRI SEP 19 2008
SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...THE 12Z MODELS ARE IN
REASONABLE AGREEMENT WITH THE SLOW EWD PROGRESSION THE CENTRAL U.S.
MID/UPPER TROUGH. THIS WILL MAINTAIN A GENERAL SWLY FLOW ALOFT OVER
THE SERN U.S. EMBEDDED WITHIN THIS FLOW WILL BE SEVERAL
DISTURBANCES, WHICH WILL AID IN THE CONVECTIVE DEVELOPMENT DURING
THE PERIOD. THE STRONG SURFACE HIGH CENTERED OVER NEW ENGLAND WILL
MOVE ENE INTO THE NRN ATLANTIC THIS WEEKEND, WITH ITS RIDGE EXTENDING
SWWD ALONG THE LEE OF THE APPALACHIANS INTO THE SERN STATES.
MEANWHILE, LOW PRESSURE NE OF THE BAHAMAS WILL MOVE TOWARD THE
MID-ATLANTIC COAST. THIS SYNOPTIC PATTERN FAVORS A CONTINUATION OF
THE E-NE LOW LEVEL FLOW. WITH REGARDS TO LOW PRESSURE DEVELOPMENT IN
THE WRN GOMEX, BOTH THE GFS AND ECMWF DO NOT DEVELOP A CLOSED
CIRCULATION, WHILE THE NAM DOES. THE NAM REMAINS THE DRIER OF THE
THREE SOLUTIONS, WITH THE GFS AND ECMWF FAIRLY SIMILAR IN THEIR
MOISTURE FIELDS. FOR SENSIBLE WEATHER, EXPECT SILENT 10 POPS FOR ALL
BUT THE FAR WRN, ERN AND COASTAL ZONES BOTH SATURDAY AND SATURDAY
NIGHT. MOISTURE INCREASES, ESPECIALLY FOR THE SERN HALF OF THE CWA
ON SUNDAY AND SUNDAY NIGHT AS WEAK DISTURBANCES RIDE NEWD ALONG A
STALLED FRONT OVER THE NERN GOMEX. WITH THE PAST CONSISTENCY OF THE
GFS, WILL FAVOR THE MAVMOS POPS AND TEMPS DURING THE PERIOD.
LONG TERM (MONDAY THROUGH FRIDAY)...SURFACE WINDS WILL CONTINUE FROM
THE EAST TO NORTHEAST THROUGH THE PERIOD. WEAK UPPER TROUGHING WILL
RESIDE OVER THE LOCAL AREA THROUGH TUESDAY BECOMING MORE PRONOUNCED
WEDNESDAY THROUGH FRIDAY AS A CLOSED UPPER LOW DEVELOPS OVER THE MID
ATLANTIC STATES AND LIFTS TOWARD NEW ENGLAND. AS THE TROUGH DEEPENS,
TIME HEIGHT CROSS SECTIONS DEPICT A MUCH DRIER AIRMASS FILTERING IN
THE MID/UPPER LEVELS. POPS WILL BE IN THE CHANCE CATEGORY FOR MONDAY
AND TUESDAY DIMINISHING TO SLIGHT TO NIL FOR THE MIDDLE TO LATE WEEK
PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 66 88 67 88 69 / 10 10 10 30 30
PANAMA CITY 69 87 69 87 69 / 10 10 10 30 30
DOTHAN 63 84 64 84 64 / 10 10 10 20 20
ALBANY 64 85 64 85 65 / 05 10 10 20 20
VALDOSTA 64 86 65 86 66 / 10 10 10 30 30
CROSS CITY 66 88 67 88 69 / 10 20 20 40 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
AVIATION...GODSEY
PREVIOUS DISCUSSION...JAMSKI/BARRY
REST OF DISCUSSION...WOOL
000
FXUS62 KMFL 192329
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
729 PM EDT FRI SEP 19 2008
.AVIATION...DOPPLER RADAR SHOWING SCT-NMRS SHWRS OVER ATLC WATERS
MOVING SOUTHWEST. WL EXPECT A FEW OF THESE TO PASS CLOSE TO ERN
TERMINALS CLOSEST TO THE COAST THROUGH 06Z BUT DISSIPATING BEFORE
REACHING KTMB. SFC WINDS SHOULD GRADUALLY DECREASE TO 5-10 KTS BY
06Z. VFR CONDITIONS SHOULD REMAIN OVR KAPF THROUGH THE ENTIRE
FORECAST PERIOD. SFC WINDS SHOULD BE MORE EASTERLIES AND NOT AS
GUSTY OVER ERN TERMINALS SATURDAY, HOWEVER, EXPECT SHOWER ACTIVITY
CURRENTLY OVER ATLC WATERS/NRN BAHAMAS TO BE ADVECTED WESTWARD AND
SO WILL INDICATE VCSH AGAIN IN THE TAFS FOR SAT MORNING. GUIDANCE
SUGGEST TSTM ACTIVITY OVER ERN AREAS EARLY SATURDAY AFTERNOON, SO
WL INDICATE VCTS FOR ALL ERN TERMINALS STARTING AT 17Z BUT EXPECT
SEA BREEZE WL PUSH ALL ACTIVITY INLAND AWAY FROM THE TERMINALS
(EXCEPT KTMB) BY 20Z.
&&
.PREV DISCUSSION... /ISSUED 314 PM EDT FRI SEP 19 2008/
DISCUSSION...THIS MORNINGS RAOB COMBINED WITH THE CURRENT MIMIC-
TPW IMAGES SHOW DRIER AIR STILL MOVING SOUTH TOWARDS EXTREME SOUTH
FLORIDA. 88-D SHOWS ISOLATED TO WIDELY SCATTERED SHOWERS MOVING
SOUTHWEST. HAD TO CHANGES THE POPS FOR THE REST OF TODAY FROM 40 PERCENT
TO AT MOST 20 PERCENT. IN THE SHORT TERM, THE GFS40 WANTS TO MOVE
A TROUGH AND ASSOCIATED MOISTURE WEST FROM THE CENTRAL BAHAMAS BY
SAT AND SAT NGT BUT THE NAM12 SHOWS A VERY SLOW MOVEMENT WESTWARD.
HAVE SPLIT THE DIFFERENCE THROUGH SUNDAY AND WENT LOW CHC POPS.
THE NAM12 FINALLY SHOWS THE MOISTURE AND TROUGH REACHING SOUTH
FLORIDA BY MONDAY. I INHERITED GOOD POPS WITH AN INCREASE BY MON
SO THIS LOOKS GOOD. GFS40 MEAN RH RISES BY TUE AND WENT CLOSE TO
MEXMOS WITH A HIGHER END CHANCE CATEGORY.
ALSO IN THE SHORT TERM, A MID LEVEL TROUGH DEEPENS OVER THE
WEEKEND AND DEVELOPS A LOW OFF THE CAROLINA COAST BY FRIDAY BUT AS
THE MID LEVEL LOW MOVES NORTH AND WEAKENS, THE ATLANTIC LOW MOVES
NORTH A WEAKENS ALSO. IN THE MEANTIME, A DECENT NORTHEAST FLOW
EXISTS OVER THE SOUTHEAST UNITED STATES UNTIL THE LOW WEAKENS SUN NGT.
THIS WILL SEND SOME SWELLS SOUTHWARD INTO FLORIDA. AN EVEN STRONGER
NE FLOW DEVELOPS MID WEEK TO THE WEST OF AN INVERTED TROUGH.
MARINE...WINDS WILL BE NE-E 5 TO 10 KNOTS WITH SEAS 2 TO 4 FEET
THROUGH SUN NGT EXCEPT TO 4 FEET PALM BEACH WATERS SAT NGT DUE TO
3 FOOT SWELLS. WAVES AND SWELLS DECREASE BY MONDAY OVER THE
ATLANTIC TO LESS THAN 4 FEET. WINDS WILL BE A BIT STRONGER OVER
THE GULF OF MEXICO THROUGH SAT AND ON WED.
FIRE WEATHER...NO CONCERNS HERE AS THE RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 89 77 89 / 20 30 30 40
FORT LAUDERDALE 78 90 79 89 / 20 30 30 30
MIAMI 77 90 78 90 / 20 30 30 30
NAPLES 74 91 74 90 / 10 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...70/DD
SHORT TERM/AVIATION...47/RHG
000
FXUS62 KJAX 192315
AFDJAX
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE JACKSONVILLE FL
715 PM EDT FRI SEP 19 2008
.UPDATE...SENT FORECAST UPDATE TO REMOVE LAKE WIND ADVISORY AS
WINDS DIMINISH. ADJUSTED POPS THIS EVENING SLIGHTLY TO REFLECT
GREATER INLAND PENETRATION OF SHOWERS ACRS COASTAL COUNTIES OF
SE GA/NE FL...AND FEW TSRA ALONG COAST AND OVER COASTAL WATERS.
RANGED POPS FROM 40 IMMEDIATE COAST TO 20-30 WELL INLAND. MAY
SEE SHRA COVERAGE DECREASE DURING THE EVENING...WILL RE-EVALUATE
DURING THE EVENING.
&&
.AVIATION...HAVE OVERHAULED TAF PACKAGE AS LATEST MODEL TRENDS
INDICATE MVFR CEILINGS WILL PREVAIL BEGINNING LATE THIS
AFTERNOON/EARLY EVENING AND CONTINUE OVERNIGHT. THIS IS DUE TO
NORTHERLY WINDS AT THE SURFACE BECOMING EASTERLY AROUND 3 KFT. VFR
CEILINGS ARE FORECAST AFTER 13Z.
&&
.MARINE...HAVE KEPT SCA HEADLINES AS-IS...WITH SCA FOR THE NEARSHORE
WATERS TONIGHT AND FOR THE OFFSHORE LEGS THROUGH SATURDAY.
NORTHEASTERLY GRADIENT WILL REMAIN TIGHT THROUGH NEXT WEEK AS HIGH
PRESSURE HOLDS NORTH OF THE AREA WITH SERIES OF LOW PRESSURE AREAS
DEVELOPING OVER THE WESTERN ATLANTIC. THERE MAY BE A REPRIEVE FROM
THE WINDS EARLY NEXT WEEK BETWEEN SYSTEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 83 62 85 / 0 10 0 30
SSI 68 80 69 82 / 40 30 20 30
JAX 68 82 68 84 / 30 30 20 40
SGJ 71 82 71 83 / 30 40 30 60
GNV 64 85 65 87 / 0 30 10 50
OCF 66 86 67 87 / 0 30 10 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH TO ST
AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH FL OUT
20 NM.
&&
$$
WOLF/PETERSON/KEEGAN
000
FXUS62 KKEY 191951
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
351 PM EDT FRI SEP 19 2008
.DISCUSSION...
LATEST OBSERVATIONS FROM THE CUDJOE PROFILER SHOW NORTHEAST TO EAST
WINDS NEAR 15KT FROM THE SURFACE UP TO 2KM...DECREASING TO 5KT FROM
2-4KM...THEN SHIFTING TO NORTHWESTERLIES. THE LARGE SCALE PATTERN
FEATURES A SLOW-MOVING UPPER-TROPOSPHERIC SHORT-WAVE TROUGH FROM
OFFSHORE THE CAROLINAS TO THE FLORIDA KEYS. THE TROUGH AXIS IS
CURRENTLY LOCATED JUST ABOUT OVER THE KEYS...AND THE TROUGH HAS BEGUN
TO DAMPEN/WEAKEN. NEVERTHELESS...SOME DRY AIR WEST OF THE TROUGH AXIS
HAS BEGUN TO MOVE OVER THE KEYS AT MIDTROPOSPHERIC LEVELS...AND THIS
COMBINED WITH SOME CONSIDERABLE SHEAR HAS KEPT CONVECTIVE COVERAGE
AND INTENSITY BELOW WHAT WAS OBSERVED YESTERDAY. HOWEVER...SCATTERED
SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED IN CUMULUS STREAMERS
EMANATING FROM THE BAHAMIAN ISLES...FLORIDA KEYS...AND MAINLAND SOUTH
FLORIDA...PROVIDING PORTIONS OF THE MID/UPPER KEYS WITH MEASURABLE
RAINFALL.
FORECASTS -- BASIC PROGNOSTIC REASONING REMAINS SIMILAR TO THE LAST
FEW CYCLES. THE UPPER TROUGH WILL GRADUALLY DAMPEN INTO THE
WESTERLIES WITH A RATHER NONDESCRIPT AND WEAK FLOW THEN DEVELOPING
AND PERSISTING ABOVE 10000FT THROUGH MONDAY. UPPER-TROPOSPHERIC WIND
SPEEDS WILL THEN INCREASE AS A MIDLATITUDE TROUGH DIGS SOUTHWARD MID-
WEEK. IN THE LOW LEVELS...BOTH CONTINENTAL AND SUBTROPICAL OCEANIC
RIDGING WILL REMAIN WELL NORTH OF THE FLORIDA KEYS...WITH A GENERALLY
LIGHT AND MEANDERING MOIST AND UNSTABLE EASTERLY FLOW PREVAILING
LOCALLY. THIS SETUP WILL ALLOW LOCAL MESOSCALE CIRCULATIONS TO GOVERN
DAILY RAINFALL PATTERNS...AND THE FORECASTS APPROPRIATELY REFLECT
NEAR-CLIMATOLOGICAL RAIN CHANCES.
&&
.MARINE...
MODERATE NORTHEAST TO EAST BREEZES WILL PERSIST THROUGH THIS
EVENING...THEN SLACKEN LATE TONIGHT. WINDS AND SEAS WILL BE HIGHER IN
AND NEAR SCATTERED SHOWERS AND THUNDERSTORMS TONIGHT.
&&
.AVIATION...
FOR THE REST OF THIS AFTERNOON AND TONIGHT...VFR CONDITIONS WILL PREVAIL
AT THE EYW AND MTH TERMINALS...BUT A BRIEF SPELL OF MVFR CONDITIONS
IS LIKELY WITH A PASSING SHOWER OR LINGERING CLOUD LINE.
OTHERWISE...NORTHEAST TO EAST WINDS OF 10 TO OCCASIONAL 15 KNOTS
WITH GUSTS SLIGHTLY HIGHER WILL SLOWLY ABATE TO NEAR 10 KNOTS
OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
KEY WEST 79 88 79 88 / 40 30 30 30
MARATHON 79 89 79 89 / 40 30 30 30
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........KASPER
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......ROSS
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KMFL 191914
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
314 PM EDT FRI SEP 19 2008
.DISCUSSION...THIS MORNINGS RAOB COMBINED WITH THE CURRENT MIMIC-
TPW IMAGES SHOW DRIER AIR STILL MOVING SOUTH TOWARDS EXTREME SOUTH
FLORIDA. 88-D SHOWS ISOLATED TO WIDELY SCATTERED SHOWERS MOVING
SOUTHWEST. HAD TO CHANGES THE POPS FOR THE REST OF TODAY FROM 40 PERCENT
TO AT MOST 20 PERCENT. IN THE SHORT TERM, THE GFS40 WANTS TO MOVE
A TROUGH AND ASSOCIATED MOISTURE WEST FROM THE CENTRAL BAHAMAS BY
SAT AND SAT NGT BUT THE NAM12 SHOWS A VERY SLOW MOVEMENT WESTWARD.
HAVE SPLIT THE DIFFERENCE THROUGH SUNDAY AND WENT LOW CHC POPS.
THE NAM12 FINALLY SHOWS THE MOISTURE AND TROUGH REACHING SOUTH
FLORIDA BY MONDAY. I INHERITED GOOD POPS WITH AN INCREASE BY MON
SO THIS LOOKS GOOD. GFS40 MEAN RH RISES BY TUE AND WENT CLOSE TO
MEXMOS WITH A HIGHER END CHANCE CATEGORY.
ALSO IN THE SHORT TERM, A MID LEVEL TROUGH DEEPENS OVER THE
WEEKEND AND DEVELOPS A LOW OFF THE CAROLINA COAST BY FRIDAY BUT AS
THE MID LEVEL LOW MOVES NORTH AND WEAKENS, THE ATLANTIC LOW MOVES
NORTH A WEAKENS ALSO. IN THE MEANTIME, A DECENT NORTHEAST FLOW
EXISTS OVER THE SOUTHEAST UNITED STATES UNTIL THE LOW WEAKENS SUN NGT.
THIS WILL SEND SOME SWELLS SOUTHWARD INTO FLORIDA. AN EVEN STRONGER
NE FLOW DEVELOPS MID WEEK TO THE WEST OF AN INVERTED TROUGH.
&&
.MARINE...WINDS WILL BE NE-E 5 TO 10 KNOTS WITH SEAS 2 TO 4 FEET
THROUGH SUN NGT EXCEPT TO 4 FEET PALM BEACH WATERS SAT NGT DUE TO
3 FOOT SWELLS. WAVES AND SWELLS DECREASE BY MONDAY OVER THE
ATLANTIC TO LESS THAN 4 FEET. WINDS WILL BE A BIT STRONGER OVER
THE GULF OF MEXICO THROUGH SAT AND ON WED.
&&
.FIRE WEATHER...NO CONCERNS HERE AS THE RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 89 77 89 / 20 30 30 40
FORT LAUDERDALE 78 90 79 89 / 20 30 30 30
MIAMI 77 90 78 90 / 20 30 30 30
NAPLES 74 91 74 90 / 10 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...18/GR
SHORT TERM/AVIATION...30/KOB
000
FXUS62 KJAX 191902
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
230 PM EDT FRI SEP 19 2008
...STRONGER NORTHEAST FLOW EVENT POSSIBLE EARLY NEXT WEEK...
.SHORT TERM...MSAS ANALYSIS SHOWS STRONG EARLY SEASON HIGH
PRESSURE CONTINUES OVER THE NEW ENGLAND STATES WITH A 1035 MB
HIGH. RIDGING FROM THIS FEATURE EXTENDS ALL THE WAY DOWN THE MID-
ATLANTIC COASTLINE AND THROUGH THE SOUTHEAST COASTAL PLAIN
INCLUDING A GOOD PORTION OF OUR FORECAST AREA. THIS...ALONG WITH A
POST SHORTWAVE ENVIRONMENT HAS PRODUCED A NORTHEAST FLORIDA FLOW
ENVIRONMENT WHICH CONTINUES TO BE RICH WITH LOW LEVEL MOISTURE BUT
EXTREMELY DRY ALOFT.
THIS IS BEARING ITSELF OUT IN THE FORM OF QUICKLY DEVELOPING CU IN
SPEED CONVERGENT ENVIRONMENT BUT LIMITED VERTICAL EXTENT TO
CLOUDS...AN EVEN FURTHER DEPARTURE FROM PREVIOUS DAYS ACTIVITY.
EXPECT FOR THE REMAINDER OF THE AFTERNOON...CLOUDS TO CONTINUE TO
INCREASE OVER THE MAINLAND...ESPECIALLY OVER THE FLORIDA
PORTION...BUT SHRA WILL BE 20% OR LESS IN COVERAGE AND GENERALLY
CONFINED TO THE IMMEDIATE COAST. THE REAL ACTION INITIALLY WILL BE
OVER THE COASTAL WATERS WHERE SCATTERED SHRA CONTINUE TO ENCROACH
THE OFFSHORE WATERS AS THEY PROGRESS SOUTHWEST.
FOR TH OVERNIGHT PERIOD...EXPECT NEARSHORE WATERS TO INCREASE IN
COVERAGE OF SHRA ACTIVITY AS INVERTED 850-700 MB SUBTLE TROUGH
MOVES WESTWARD. ACTIVITY SHOULD REMAIN OVER THE MARINE ENVIRONMENT
WITH NEGLIGIBLE CHANCES FOR THE COASTAL AREAS.
FOR SAT...MODELS ARE NOW HONING IN ON A SOLUTION THAT INCLUDES THE
DEVELOPMENT OF AN INVERTED SURFACE TROUGH OFF THE EAST CENTRAL
FLORIDA COAST SAT AFTERNOON. DEVELOPMENT IN THIS AREA WOULD KEEP
MOST OF THE HIGH MOISTURE AWAY FROM OUR COAST AS WELL AS THE BEST
CONVERGENCE. WITH EASTERLY FLOW REGIME IN PLACE HOWEVER...STILL
ENOUGH MOISTURE CONVERGENCE TO WARRANT LOW END SCT POPS FOR THE
FLORIDA COAST PRIMARILY SAT AFTERNOON.
AS INVERTED TROUGH PROGRESSES NORTHWARD SUNDAY AFTERNOON...MOISTURE
AND CONVERGENCE WILL INCREASE IN TANDEM AND WITH SHORTWAVE ENERGY
ROTATING AROUND SOUTHEAST BROAD TROUGH...SHOULD SEE POPS INCREASE
TO HIGH END SCT FOR MOST AREAS AND LIKELY ALONG THE SOUTHEASTERN
MOST COAST. WILL ALSO SEE WINDS CONTINUE ON THE HIGH SIDE WITH
LAKE WIND ADVISORIES LIKELY TO CONTINUE INTO THE WEEKEND.
.LONG TERM...DEPENDING ON WHICH MODEL YOU BELIEVE AND RIGHT NOW IM
LEANING TOWARD THE ECMWF...LOOKS LIKE EARLY NEXT WEEK COULD BE THE
WORST OF THE LOCAL NORTHEAST FLOW EVENT...ESPECIALLY MONDAY.
SHORTWAVE ENERGY LOOKS TO DEVELOP A WAVE/LOW OFFSHORE AND ENHANCE
NORTHEAST FLOW ACROSS THE AREA AND RESULT IN CONTINUED HIGH
PRIMARILY COASTAL POPS.
&&
.AVIATION...HAVE OVERHAULED TAF PACKAGE AS LATEST MODEL TRENDS
INDICATE MVFR CEILINGS WILL PREVAIL BEGINNING LATE THIS
AFTERNOON/EARLY EVENING AND CONTINUE OVERNIGHT. THIS IS DUE TO
NORTHERLY WINDS AT THE SURFACE BECOMING EASTERLY AROUND 3 KFT. VFR
CEILINGS ARE FORECAST AFTER 13Z.
&&
.MARINE...HAVE KEPT SCA HEADLINES AS-IS...WITH SCA FOR THE NEARSHORE
WATERS TONIGHT AND FOR THE OFFSHORE LEGS THROUGH SATURDAY.
NORTHEASTERLY GRADIENT WILL REMAIN TIGHT THROUGH NEXT WEEK AS HIGH
PRESSURE HOLDS NORTH OF THE AREA WITH SERIES OF LOW PRESSURE AREAS
DEVELOPING OVER THE WESTERN ATLANTIC. THERE MAY BE A REPRIEVE FROM
THE WINDS EARLY NEXT WEEK BETWEEN SYSTEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 83 62 85 / 0 10 0 30
SSI 68 80 69 82 / 20 30 20 30
JAX 68 82 68 84 / 20 30 20 40
SGJ 71 82 71 83 / 20 40 30 60
GNV 64 85 65 87 / 0 30 10 50
OCF 66 86 67 87 / 0 30 10 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR CLAY-DUVAL-
FLAGLER-NASSAU-PUTNAM-ST JOHNS.
GA...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR COASTAL
CAMDEN-COASTAL GLYNN-INLAND CAMDEN-INLAND GLYNN.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH TO ST
AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH FL OUT
20 NM.
&&
$$
DEESE/ZAPPE/WALKER
000
FXUS62 KMLB 191803
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
200 PM EDT FRI SEP 19 2008
.DISCUSSION...
...NE SWELLS AND INCREASING THREAT FOR RIP CURRENTS EXPECTED AT THE
BEACHES THIS WEEKEND...
LATEST GFS RUN AND WATER VAPOR IMAGERY SHOWING THAT THE MID/UPPER
LEVEL DRY AIR MASS WAS MOVING ACROSS FLORIDA INTO THE ATLANTIC AND A
TROUGH OF LOW PRESSURE WAS EXTENDING FROM THE BAHAMA ISLANDS
NORTHEAST INTO THE ATLANTIC.
GUIDANCE SHOWING VORT MAXES ROUNDING THE BASE OF THE TROUGH OVER THE
CENTRAL UNITED STATES WERE STARTING TO ERODE THE UPPER RIDGE OVER
THE SOUTHEAST AND FLORIDA BUT NOT THE EASTERLY FLOW ASSOCIATED WITH
THE SURFACE HIGH PRESSURE SYSTEM WHICH REMAINS INTACT FOR AT LEAST
ANOTHER 24 HOURS. FORECAST SOUNDINGS SHOWING DEPTH OF ONSHORE FLOW
DEEP ENOUGH AND STRONG ENOUGH TO LIMIT CONVECTION TO THE WESTERN
SECTIONS OF THE FORECAST AND ONLY QUICK SHOWERS OVER THE ATLANTIC
AND COASTAL COUNTIES. 30 POP OVER THE ATLANTIC AND COASTAL COUNTIES
MAY BE A BIT OVER DONE ON SATURDAY BUT WILL TEMPER IT DOWN BY SAYING
CHC SHOWERS AND A SLGT CHC OF STORMS. ONSHORE FLOW WILL ALSO KEEP
OVERNIGHT LOWS FROM DROPPING BELOW THE MID/UPPER 70S.
SUN-MON...THE OLD FRONTAL BOUNDARY CURRENTLY WELL OFFSHORE IS
FORECAST TO BACK UP TWD THE EAST COAST LATE IN THE WEEKEND AS
ANOTHER MID LVL S/W TROUGH DEVELOPS ACROSS THE NRN GULF COAST. GFS
INDICATES MOISTURE LVLS WILL INCREASE AS THE LOW LVL INVERTED TROUGH
APPROACHES ON SUNDAY WITH NAM HOLDING OFF MUCH OF THE DEEPER
MOISTURE INCREASE UNTIL LATE SUN NGT AS INVERTED TROUGH AXIS COMES
ONSHORE LATE...WITH HIGHEST RAIN CHANCES ON MONDAY. FOR NOW WILL
KEEP MID RANGE SCATTERED POPS BOTH SUNDAY AND MONDAY THOUGH GFS MAY
BE A BIT QUICK WITH ITS MOISTURE RETURN. NE SWELLS WILL CONTINUE
ALONG THE BEACHES TO END THE WEEKEND WITH AN ELEVATED RISK OF RIP
CURRENTS.
12Z GFS A BIT MORE PROGRESSIVE WITH MID ATLC S/W NEXT WEEK PUSHING
JUST OFF THE MID ATLC COAST AS AN AREA OF DISTURBED WEATHER IS PROGD
TO MOVE WNW ACROSS THE BAHAMAS AND GREATER ANTILLES. SFC HIGH
PRESSURE ACROSS NE US WILL KEEP ONSHORE FLOW ACROSS E CENTRAL FL
WITH MOISTURE LVLS APPEARING HIGH ENOUGH TO KEEP SCATTERED POPS IN
THE FORECAST EACH DAY...SO NO CHANGES AT THIS TIME TO DAYS 4-7.
PREVIOUS EXTENDED DISCUSSION FOLLOWS...TUE-FRI...SHARP AMPLITUDE
SHORT WAVE RIDGE BUILDS IN BEHIND THE DEPARTING NRN STREAM TROUGH.
THIS TRAPS THE VORT ENERGY FROM THE CTRL-ERN CONUS TROUGH AND CAUSES
IT TO DRIFT SWD EITHER NEAR OR OFFSHORE THE NC OUTER BANKS THRU
THU...BEFORE STARTING TO LIFT BACK NWD ON FRI. 00Z ECM IS STRONGER
THAN THE GFS WITH BOTH THE H50 LOW AS WELL AS THE SFC LOW WHICH
SPINS UP ALONG THE STALLED FRONT. ECM SOLN MIGHT PORTEND SOME DRIER
AIR TRYING TO WRAP AROUND THE BACKSIDE OF THE LOW AND INTO
FL...WHILE THE FAVORED GFS SOLN IS WEAKER WITH THE LOW AND KEEPS
ECFL IN HIGHER MEAN MOISTURE. WILL CONTINUE TREND OF MID-HIGH END
SCT POPS IN A PERSISTENT MOIST ONSHORE FLOW REGIME. AS WITH THE
SHORT RANGE...THINK PROSPECTS FOR TSTMS WILL BE RATHER LIMITED GIVEN
THE MAGNITUDE OF THE ONSHORE FLOW COUPLED WITH EXTENT OF CLOUD
COVER.
&&
.AVIATION...BRIEF MVFR CONDITIONS IN/NEAR QUICK MOVING AFTERNOON AND
OVERNIGHT SHOWERS ALONG THE COAST AND NEARSHORE WATERS...AND
ISOLATED STORMS WELL INLAND/WESTERN AREAS THIS AFTERNOON.
&&
.MARINE...PRESSURE GRADIENT STRONG ENOUGH TO SUPPORT ONSHORE NE/E
WINDS TO 15-20 KNOTS AT TIMES ACROSS THE NRN AND CENTRAL WATERS
THROUGH THE WKND WITH SEAS TO 6 FEET IN A BUILDING EAST
NORTHEAST SWELL. INCREASING SWELL HEIGHT AND PERIOD WILL RESULT IN
AN ELEVATED RIP CURRENT RISK THE NEXT COUPLE OF DAYS. ONSHORE FLOW
SHOULD DECREASE TO 10-15 KTS EARLY NEXT WEEK WITH GRADUALLY
DIMINISHING SEAS INTO TUE.
&&
.HYDROLOGY...SLOW FALL TO CONTINUE OVER THE MIDDLE ST JOHNS RIVER
BASIN THRU EARLY NEXT WEEK...ALTHOUGH ALL FORECAST POINTS WILL
CONTINUE ABOVE FLOOD STAGE. FOR THE LATEST INFO ON ST JOHNS RIVER
LEVEL SEE THE RIVER FLOOD STATEMENT /MIAFLSMLB/.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 70 84 72 85 / 20 30 20 50
MCO 70 87 72 87 / 20 30 20 50
MLB 74 85 73 86 / 20 30 20 50
VRB 73 86 72 87 / 20 30 20 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...WIMMER
LONG TERM....VOLKMER
000
FXUS62 KTAE 191800
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
200 PM EDT FRI SEP 19 2008
.SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...THE 12Z MODELS ARE IN
REASONABLE AGREEMENT WITH THE SLOW EWD PROGRESSION THE CENTRAL U.S.
MID/UPPER TROUGH. THIS WILL MAINTAIN A GENERAL SWLY FLOW ALOFT OVER
THE SERN U.S. EMBEDDED WITHIN THIS FLOW WILL BE SEVERAL
DISTURBANCES, WHICH WILL AID IN THE CONVECTIVE DEVELOPMENT DURING
THE PERIOD. THE STRONG SURFACE HIGH CENTERED OVER NEW ENGLAND WILL
MOVE ENE INTO THE NRN ATLANTIC THIS WEEKEND, WITH ITS RIDGE EXTENDING
SWWD ALONG THE LEE OF THE APPALACHIANS INTO THE SERN STATES.
MEANWHILE, LOW PRESSURE NE OF THE BAHAMAS WILL MOVE TOWARD THE
MID-ATLANTIC COAST. THIS SYNOPTIC PATTERN FAVORS A CONTINUATION OF
THE E-NE LOW LEVEL FLOW. WITH REGARDS TO LOW PRESSURE DEVELOPMENT IN
THE WRN GOMEX, BOTH THE GFS AND ECMWF DO NOT DEVELOP A CLOSED
CIRCULATION, WHILE THE NAM DOES. THE NAM REMAINS THE DRIER OF THE
THREE SOLUTIONS, WITH THE GFS AND ECMWF FAIRLY SIMILAR IN THEIR
MOISTURE FIELDS. FOR SENSIBLE WEATHER, EXPECT SILENT 10 POPS FOR ALL
BUT THE FAR WRN, ERN AND COASTAL ZONES BOTH SATURDAY AND SATURDAY
NIGHT. MOISTURE INCREASES, ESPECIALLY FOR THE SERN HALF OF THE CWA
ON SUNDAY AND SUNDAY NIGHT AS WEAK DISTURBANCES RIDE NEWD ALONG A
STALLED FRONT OVER THE NERN GOMEX. WITH THE PAST CONSISTENCY OF THE
GFS, WILL FAVOR THE MAVMOS POPS AND TEMPS DURING THE PERIOD.
&&
.LONG TERM (MONDAY THROUGH FRIDAY)...SURFACE WINDS WILL CONTINUE
FROM THE EAST TO NORTHEAST THROUGH THE PERIOD. WEAK UPPER TROUGHING
WILL RESIDE OVER THE LOCAL AREA THROUGH TUESDAY BECOMING MORE
PRONOUNCED WEDNESDAY THROUGH FRIDAY AS A CLOSED UPPER LOW DEVELOPS
OVER THE MID ATLANTIC STATES AND LIFTS TOWARD NEW ENGLAND. AS THE
TROUGH DEEPENS, TIME HEIGHT CROSS SECTIONS DEPICT A MUCH DRIER
AIRMASS FILTERING IN THE MID/UPPER LEVELS. POPS WILL BE IN THE
CHANCE CATEGORY FOR MONDAY AND TUESDAY DIMINISHING TO SLIGHT TO NIL
FOR THE MIDDLE TO LATE WEEK PERIOD.
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL FOR THE REMAINDER OF THIS
AFTERNOON AND EVENING AT ALL TERMINALS. SOMEWHAT MOIST EAST TO
NORTHEAST FLOW OVERNIGHT MAY BRING IN SOME MVFR CIGS BY SUNRISE.
CONTINUED INFLUX OF MOISTURE DURING THE DAY SATURDAY WILL KEEP THE
CHANCE FOR MVFR CIGS INTACT.
&&
.MARINE...A HIGH PRESSURE RIDGE WILL REMAIN ANCHORED TO THE
NORTHEAST OF THE WATERS THROUGH THE WEEKEND WHICH WILL MAINTAIN THE
MODERATE EAST TO NORTHEAST WIND FLOW. THIS FLOW WILL STRENGTHEN AS
LOW PRESSURE DEVELOPS OFF THE SOUTHEAST COAST THIS WEEKEND. WINDS
AND SEAS WILL INCREASE TO EXERCISE CAUTION CRITERIA AT TIMES,
ESPECIALLY OVER THE OFFSHORE LEGS DURING THE LATE NIGHT AND EARLY
MORNING HOURS THROUGH SATURDAY NIGHT. WINDS AND SEAS WILL BEGIN TO
DECREASE ON SUNDAY AS THE HIGH AND LOW PRESSURE SYSTEMS LOSE THEIR
INFLUENCE ON THE LOCAL GRADIENT.
&&
.FIRE WEATHER...SOME INLAND AREAS THIS AFTN WILL SEE RH VALUES FALL
BELOW 40 PERCENT, HOWEVER RED FLAG CRITERIA WILL NOT BE MET. ENOUGH
MOISTURE IN THE EAST TO NORTHEAST FLOW TO KEEP RH VALUES ABOVE
CRITICAL LEVELS FOR THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 66 88 67 88 69 / 10 10 10 30 30
PANAMA CITY 69 87 69 87 69 / 10 10 10 30 30
DOTHAN 63 84 64 84 64 / 10 10 10 20 20
ALBANY 64 85 64 85 65 / 05 10 10 20 20
VALDOSTA 64 86 65 86 66 / 10 10 10 30 30
CROSS CITY 66 88 67 88 69 / 10 20 20 40 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
JAMSKI/CAMP/BARRY
000
FXUS62 KTBW 191751
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
151 PM EDT FRI SEP 19 2008
.SHORT TERM (TONIGHT - SUNDAY)...SOME MID/UPPER LEVEL TROUGHING
WILL REMAIN OVER THE EASTERN U.S. OVER THE WEEKEND WITH RIDGING
TRYING TO BUILD WEST FROM THE ATLANTIC OCEAN. AT THE
SURFACE...HIGH PRESSURE WILL CONTINUE TO RIDGE SOUTH SOUTHWEST
FROM THE NORTHEAST U.S. DOWN INTO FLORIDA WITH A SERIES OF LOW
PRESSURE AREAS DEVELOPING ALONG THE STALLED OUT BOUNDARY OVER THE
WESTERN ATLANTIC. THIS PATTERN WILL CONTINUE THE BREEZY NORTHEAST
TO EAST FLOW THROUGH SATURDAY... THEN THE WINDS WILL SHIFT TO A
MORE EAST TO SOUTHEAST DIRECTION AND SUBSIDE SOME FOR SUNDAY.
MOISTURE WILL BEGIN TO INCREASE OVER THE WEEKEND WITH PRECIPITABLE
WATER VALUES CLIMBING TO 1.6 TO 1.8 INCHES FROM NORTH TO SOUTH ON
SATURDAY AND TO NEAR 2 INCHES EVERYWHERE ON SUNDAY. THIS COMBINED
WITH DAYTIME HEATING COULD LEAD TO A FEW SHOWERS AND THUNDERSTORMS
ON SATURDAY...BUT THE WEST COAST SEA BREEZE WILL BE PINNED TO THE
COAST SO ONLY EXPECT 20 TO 30 PERCENT CHANCES AT THIS TIME. ON
SUNDAY WITH THE WINDS DIMINISHING SOME THE WEST COAST SEA BREEZE
SHOULD BE ABLE TO MOVE INLAND AND THIS COMBINED WITH THE INCREASED
MOISTURE AND DAYTIME HEATING SHOULD LEAD TO BETTER CHANCES OF
SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA.
TEMPERATURES WILL REMAIN NEAR NORMAL THROUGH THE PERIOD WITH LOWS
MOSTLY IN THE UPPER 60S TO MID 70S...AND DAYTIME HIGHS IN THE MID
80S TO LOWER 90S.
.LONG TERM (SUNDAY NIGHT - FRIDAY)...WEAKENING HIGH PRESSURE OVER
THE REGION WILL KEEP LIGHT SOUTHWESTERLY WINDS FOR THE BEGINNING OF
THE WEEK WHICH WILL ALLOW FOR SEA BREEZE CIRCULATIONS TO DEVELOP
EACH AFTERNOON THROUGH TUESDAY. ON TUESDAY NIGHT A DISSIPATING
WEAKENING TROUGH TO THE SOUTHEAST OF THE STATE WILL BEGIN MOVING
BACK INTO THE AREA...BRINGING INCREASING MOISTURE AND CLOUD COVER
AND ENSURING CHANCES FOR SCATTERED SHOWERS THROUGH THE END OF THE
WORK WEEK. GFS/MOS GUIDANCE ARE BACKING DOWN FROM PREVIOUS TRENDS
OF SWITCHING SURFACE WINDS TO A MORE NW FLOW AROUND MIDWEEK AND
KEEPING IT FROM THE NE FOR MUCH OF THE LONG TERM AS A RIDGE OVER
THE EASTERN SEABOARD SLOWLY DROPS SOUTH AND STRENGTHENS. PRESSURE
GRADIENTS OVER THE STATE SEEM TO INCREASE IN RESPONSE TO THE
APPROACHING RIDGE AND SURFACE WINDS BEGIN INCREASING BY
WEDNESDAY..THUS MINIMIZING SEA BREEZE DEVELOPMENT. THIS GENERAL
SCENARIO WILL TRANSLATE INTO HAVING THUNDERSTORM ACTIVITY
DEVELOPING NEAR THE COAST EARLY IN THE AFTERNOON AND THEN PUSHING
INLAND THROUGH THE EARLY EVENING HOURS ON MONDAY AND TUESDAY. THEN
ON WEDNESDAY AND BEYOND...NE FLOW DOMINATES DURING THE DAY WHICH
WILL ALLOW FOR THUNDERSTORMS TO DEVELOP INLAND THEN MOVING TOWARDS
THE COAST LATER IN THE AFTERNOON.
IN GENERAL...EXPECT EASTERLY AND NORTHEASTERLY FLOW TO PREVAIL WITH
CLIMO 30 TO 50 POPS THROUGH MUCH OF THE FORECAST PERIOD. AFTERNOON
HIGHS BEGIN TO STALL AROUND THE 87 TO 89 MARK...ALONG WITH LOWS
RANGING FROM THE UPPER 60S NORTH THROUGH LOWER/MID 70S ELSEWHERE.
&&
.AVIATION...VFR CONDITIONS EXPECTED TO PREVAIL FOR THE REST OF THE
AFTERNOON AT ALL TAF SITES. FMY AND RSW WILL EXPERIENCE AFTERNOON
PERIODS OF WINDS IN THE 12 TO 15 KNOT RANGE WITH POSSIBLE GUSTS TO
20 KNOTS...DROPPING BELOW 10 KNOTS IN THE EVENING AND OVERNIGHT. VFR
SHOULD CONTINUE ON SATURDAY WITH NO AVIATION WEATHER ISSUES EXPECTED
UNTIL MAYBE AFTERNOON WHEN SOME ISOLATED TO SCATTERED
THUNDERSTORMS TO CAUSE SOME MVFR/LOCAL IFR CONDITIONS.
&&
.MARINE...NORTHEAST TO EAST FLOW WILL CONTINUE THROUGH THE
FORECAST...EXCEPT A LITTLE MORE EAST TO SOUTHEAST ON SUNDAY. WILL
CONTINUE TO SEE A NOCTURNAL INCREASE IN THE WINDS OVER THE COASTAL
WATERS THROUGH EARLY NEXT WEEK. SPEEDS COULD APPROACH EXERCISE
CAUTION CRITERIA EACH NIGHT...ESPECIALLY FROM TAMPA BAY NORTH...
THEN DECREASE EACH AFTERNOON WITH THE SEA BREEZE DEVELOPING NEAR THE
COAST SUNDAY THROUGH TUESDAY.
&&
.FIRE WEATHER...NO HEADLINES OR HIGHLIGHTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 73 89 73 88 / 10 20 20 40
FMY 72 91 73 90 / 10 30 20 40
GIF 70 89 71 89 / 10 30 20 50
SRQ 72 89 72 88 / 10 20 20 40
BKV 68 88 69 87 / 10 20 20 40
SPG 75 89 77 88 / 10 20 20 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/MARINE/FIRE...PRC
LONG TERM/AVIATION....AR
000
FXUS62 KMFL 191729
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
129 PM EDT FRI SEP 19 2008
.AVIATION...
LOW LEVEL NE WIND FLOW IS STRONGER THAN MODEL GUIDANCE HAD EARLIER
SUGGESTED AND THUS CONVECTION NOT ABLE TO REALLY GET FIRED. SO
HAVE TAKEN OUT ALL MENTION OF VCTS FOR THE E CST TERMINALS THROUGH
THE PERIOD WITH ONLY VCSH. DECENT INSTABILITY PERSISTS ENOUGH TO
KEEP VCTS IN FOR THE KAPF TAF ALTHOUGH DELAYED IT UNTIL 20Z ENDING
BY 00Z. THE NE FLOW 12KT OR GREATER ALONG E CST WILL DIMINISH AFT
00Z TO 02Z THIS EVENING INCREASING ONCE AGAIN AFT 14Z SATURDAY.
THIS WILL ALSO PREVENT W CST SEA BREEZE FROM DEVELOPING.
30/KOB
&&
.PREV DISCUSSION... /ISSUED 937 AM EDT FRI SEP 19 2008/
UPDATE...AFTER LOOKING AT 12Z SOUNDINGS AT MIA AND UPSTREAM TPA
COMBINED WITH THE MIMIC-TPW, THE MID/UPPER LVL TROUGH HAS BROUGHT
DRY AIR ALL THE WAY THROUGH THE SOUTHERN PENINSULA AND DRIER AS
YOU GO NORTH. HAVE DECIDED TO DROP THE 40% TO 30% FOR THE
NORTHWEST AND NORTH SECTIONS OF THE CWA AND LEFT IN 40% REST OF
AREA (LOWER THAN MAVMOS SOUTHEAST). THE CONVECTIVE WORKSHEET WASN`T
IMPRESSIVE CONSIDERING ALL THE UPPER DRY AIR AND GAVE US ONLY THE
LOWER 30S FOR WIND GUSTS IN STORMS BUT THE INSTABILITY STILL
REMAINED. SO POPS ARE THE ONLY CHANGE (MINOR) TO THE ZFP.
PREV DISCUSSION... /ISSUED 723 AM EDT FRI SEP 19 2008/
AVIATION...
MOSTLY VFR CONDITIONS ARE ANTICIPATED ACROSS S FLA THROUGH THE
NEXT 24 HOURS. A QUICK PASSING SHRA MAY BE POSSIBLE ALONG THE E
CST THIS MORNING BUT ANY LOWERING OF CIG/VSBY TO MVFR WILL ONLY BE
FOR LESS THAN 15 MINUTES. SCT TSRA WILL DEVELOP AFT 14Z WITH LOW
LEVEL NE FLOW STEERING CONVECTION INLAND AWAY FROM THE E CST AND
HAVE ONLY PLACED VCTS IN THE TAFS. THE THREAT REMAINS LOW ENOUGH
EVEN THOUGH SOME OF THE STORMS WILL MOVE TO THE SW CST HAVE ONLY
PLACED VCSH IN THE TAF FOR KAPF. THE NE FLOW WILL PICK UP TO
AROUND 12KT ALONG THE E CST AFT 13Z AND THIS WILL PREVENT A W CST
SEA BREEZE FROM DEVELOPING.
30/KOB
PREV DISCUSSION... /ISSUED 311 AM EDT FRI SEP 19 2008/
DISCUSSION...THE UNSEASONABLE DEEP UPPER TROUGH ALONG THE U.S. E
SEA BOARD HAS MOVED E INTO THE ATLC. A SHORT WAVE RIDGE EXTENDING
FROM THE NE GULF OF MEX N INTO THE OH RIVER VALLEY MOVES E OVER THE
FLA PENINSULA TODAY AND TONIGHT AS ANOTHER UPPER LOW DIGS INTO THE
MID MS RIVER VALLEY. THIS UPPER LOW BECOMES CUT OFF FROM THE UPPER
FLOW AND MEANDERS NORTHWARD AND WEAKENS OVER THE UPPER MIDWEST MON.
A LONG WAVE RIDGE DEVELOPS AND EXTENDS FROM THE GULF OF MEX TO N OF
THE GREAT LAKES TUE...MOVING E TO NEW ENGLAND WITH A CLOSED UPPER
LOW FORMING OVER THE MID ATLC STATES WED AND THU.
FOR THE SHORT TERM...TODAY THROUGH SUN...ATMOSPHERE A BIT DRIER BUT
SCATTERED POPS STILL EXPECTED...MAINLY ALONG THE E COAST THIS
MORNING AND IN THE INTERIOR AND W THIS AFTERNOON. SOME E COAST
NOCTURNAL SHOWERS TONIGHT. RIDGE OVER THE AREA SAT INTO SUN PUTS A
DRY MID LEVEL CAPPING LAYER OVER S FLA AND POPS AGAIN A BIT LOWER.
EXTENDED PERIOD...MON THROUGH THU...GRADUAL MOISTENING THE
ATMOSPHERE OCCURS AS A WEAK SURFACE TROUGH CURRENTLY OVER THE
BAHAMAS MOVES OVER S FLA. SCATTERED POPS EXPECTED WITH NEAR NORM
TEMPS.
MARINE...WINDS NE 10 TO 15 KNOTS TODAY DUE TO LOW PRES DEVELOPING
WELL OFF OF THE COAST E OF JAX. WINDS BECOME E TONIGHT INTO THE
WEEKEND AND DECREASE TO 10 KNOTS. WINDS BACK TO 10 TO 15 KNOTS NEXT
WEEK. GULF STREAM SEAS TO 5 FEET TODAY BUT BECOMING 4 FEET OR LESS
THE REMAINDER OF THE PERIOD. AT TIMES EARLY NEXT WEEK.
FIRE WEATHER...MINIMUM RH ABOVE CRITICAL VALUES THROUGH THE PERIOD.
NO PROBLEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 89 76 87 / 20 30 30 40
FORT LAUDERDALE 78 88 78 88 / 20 30 30 30
MIAMI 77 89 77 89 / 20 30 30 30
NAPLES 74 90 73 91 / 10 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
000
FXUS62 KKEY 191516
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1116 AM EDT FRI SEP 19 2008
.DISCUSSION...
FORECASTS HAVE BEEN UPDATED TO REDUCE RAIN CHANCES/SKY COVER AND
INCREASE WINDS. THE SHORT WAVE TROUGH WHICH WAS OVER THE NORTHEASTERN
GULF OF MEXICO AND NORTHERN FLORIDA YESTERDAY AT THIS TIME HAS MOVED
SOUTHEASTWARD...AND THE TROUGH AXIS NOW RUNS FROM OFFSHORE THE
CAROLINAS TO NEAR THE KEYS. SHORT-WAVE RIDGING AND ASSOCIATED HEIGHT
RISES IN THE WAKE OF THIS TROUGH FROM GEORGIA SOUTHWARD OVER THE
EASTERN GULF OF MEXICO AND MOST OF THE FLORIDA PENINSULA HAVE
FORTIFIED THE SOUTHERN PORTION OF A SPRAWLING CONTINENTAL SURFACE
ANTICYCLONE. MEANWHILE...LOWER PRESSURES STILL PREVAIL OVER THE
BAHAMAS. THE SYNOPTIC GRADIENT FLOW HAS THUS INCREASED OVER THE KEYS
BETWEEN THE SURFACE HIGH PRESSURE TO THE NORTH AND LOWER PRESSURE
OVER THE BAHAMAS. ALSO...DRIER MIDTROPOSPHERIC AIR HAS MOVED IN OVER
SOUTHERN FLORIDA AND IS SUPPRESSING CONVECTIVE DEVELOPMENT AT THIS
TIME. CONDITIONS MAY BECOME MORE FAVORABLE FOR CONVECTION IN CLOUD
LINES AND ALONG SEA BREEZES LATE THIS AFTERNOON. HOWEVER...GRADIENT
FLOW WILL HAVE TO DECREASE FIRST. IN ANY CASE...IT LOOKS LIKE SHOWER
AND THUNDERSTORM COVERAGE WILL BE MUCH LESS THAN YESTERDAY OR THE
DAY BEFORE.
&&
.MARINE...
NORTHEAST TO EAST BREEZES HAVE FRESHENED CONSIDERABLY AND WILL RUN
NEAR 15KT WITH FREQUENT GUSTS NEAR 20KT FOR THE AT LEAST THE REST OF
THE AFTERNOON. WINDS SHOULD SLACKEN SOME AFTER DARK.
&&
.AVIATION...
FOR THE BALANCE OF TODAY...VFR CONDITIONS WILL PREDOMINATE AT THE
EYW AND MTH TERMINALS...WHILE DRIER AIR AND A STEADY NORTHEAST WIND
OF 10 TO 15 KNOTS WILL PROVIDE A SIGNIFICANT VERTICAL CHALLENGE FOR
ANY CLOUD LINE FORMATION.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........KASPER
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......FUENTES
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KJAX 191356
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
956 AM EDT FRI SEP 19 2008
.PUBLIC...SURFACE FEATURES INCLUDE LARGE HIGH PRESSURE SYSTEM OVER
THE EASTERN UNITED STATES WITH LOW PRESSURE WELL TO OUR EAST. ALOFT...
SHORTWAVE TROUGH IS POSITIONED JUST OFFSHORE WITH WATER VAPOR IMAGERY
INDICATING VERY DRY CONDITIONS. IN FACT...KJAX MORNING SOUNDING
INDICATED PWAT AROUND 1 INCH WITH VERY DRY CONDITIONS ABOVE 850
MB. MOISTURE DEPTH WILL REMAIN SHALLOW THROUGH AT LEAST TONIGHT AS
LOW LEVEL FLOW GRADUALLY VEER FROM THE NORTH TO NORTHEAST. LOW-
LEVEL CLOUDS WILL INCREASE ACROSS NORTHEAST FLORIDA AND MAINLY
COASTAL SOUTHEAST GEORGIA BY EARLY AFTERNOON DUE TO ISENTROPIC
PROCESSES. WITH AN ESTABLISHING NORTHEAST FLOW REGIME...A FEW
COASTAL SHOWERS WILL LIKELY ESTABLISH THIS AFTERNOON WITH
POSSIBILITY OF THESE SHOWERS WORKING ONSHORE ACROSS NORTHEAST
FLORIDA AND COASTAL SOUTHEAST GEORGIA LATE IN THE DAY. SHOWERS
WILL BE LOW-TOPPED WITH PRONOUNCED SUBSIDENCE INVERSION...THUS
HAVE REMOVED THUNDERSTORM WORDING.
&&
.AVIATION...ALTHOUGH VFR CONDITIONS WILL LIKELY PREVAIL TODAY...
LOW-LEVEL CLOUDS WILL INCREASE AS THE DAY PROGRESSES. THESE CLOUDS
WILL INITIALLY DEVELOP DUE TO ISENTROPIC PROCESSES WITH VEERING
WINDS BETWEEN SURFACE TO NEAR 850 MB. OCCASIONAL CEILINGS AROUND 4
KFT WILL LIKELY ESTABLISH BY 17Z...POSSIBLY LOWERING TO NEAR 3 KFT
THEREAFTER.
&&
.MARINE...WILL MAINTAIN SCA HEADLINES AS NORTHEAST GRADIENT
REMAINS TIGHT. CONDITIONS WILL INITIALLY IMPROVE OVER THE
NEAR-SHORE WATERS TONIGHT AS LOW PRESSURE WELL OFFSHORE BEGINS TO
VENTURE NORTH...WITH CONDITIONS OVER THE OFFSHORE WATERS
IMPROVING ON SATURDAY. AT 13Z...BUOY 41008 INDICTED SUSTAINED NORTHEAST
WINDS OF 19 KNOTS WITH COMBINED SEAS OF 6 FEET. BUOY 41012 SHOWED
SUSTAINED WINDS OF 17 KNOTS WITH 4 FT COMBINED SEAS.
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR CLAY-DUVAL-
FLAGLER-NASSAU-PUTNAM-ST JOHNS.
GA...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR COASTAL
CAMDEN-COASTAL GLYNN-INLAND CAMDEN-INLAND GLYNN.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH TO ST
AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH FL OUT
20 NM.
&&
$$
ZAPPE/WALKER
000
FXUS62 KMFL 191338
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
937 AM EDT FRI SEP 19 2008
.UPDATE...AFTER LOOKING AT 12Z SOUNDINGS AT MIA AND UPSTREAM TPA
COMBINED WITH THE MIMIC-TPW, THE MID/UPPER LVL TROUGH HAS BROUGHT
DRY AIR ALL THE WAY THROUGH THE SOUTHERN PENINSULA AND DRIER AS
YOU GO NORTH. HAVE DECIDED TO DROP THE 40% TO 30% FOR THE
NORTHWEST AND NORTH SECTIONS OF THE CWA AND LEFT IN 40% REST OF
AREA (LOWER THAN MAVMOS SOUTHEAST). THE CONVECTIVE WORKSHEET WASN`T
IMPRESSIVE CONSIDERING ALL THE UPPER DRY AIR AND GAVE US ONLY THE
LOWER 30S FOR WIND GUSTS IN STORMS BUT THE INSTABILITY STILL
REMAINED. SO POPS ARE THE ONLY CHANGE (MINOR) TO THE ZFP.
&&
.PREV DISCUSSION... /ISSUED 723 AM EDT FRI SEP 19 2008/
AVIATION...
MOSTLY VFR CONDITIONS ARE ANTICIPATED ACROSS S FLA THROUGH THE
NEXT 24 HOURS. A QUICK PASSING SHRA MAY BE POSSIBLE ALONG THE E
CST THIS MORNING BUT ANY LOWERING OF CIG/VSBY TO MVFR WILL ONLY BE
FOR LESS THAN 15 MINUTES. SCT TSRA WILL DEVELOP AFT 14Z WITH LOW
LEVEL NE FLOW STEERING CONVECTION INLAND AWAY FROM THE E CST AND
HAVE ONLY PLACED VCTS IN THE TAFS. THE THREAT REMAINS LOW ENOUGH
EVEN THOUGH SOME OF THE STORMS WILL MOVE TO THE SW CST HAVE ONLY
PLACED VCSH IN THE TAF FOR KAPF. THE NE FLOW WILL PICK UP TO
AROUND 12KT ALONG THE E CST AFT 13Z AND THIS WILL PREVENT A W CST
SEA BREEZE FROM DEVELOPING.
30/KOB
PREV DISCUSSION... /ISSUED 311 AM EDT FRI SEP 19 2008/
DISCUSSION...THE UNSEASONABLE DEEP UPPER TROUGH ALONG THE U.S. E
SEA BOARD HAS MOVED E INTO THE ATLC. A SHORT WAVE RIDGE EXTENDING
FROM THE NE GULF OF MEX N INTO THE OH RIVER VALLEY MOVES E OVER THE
FLA PENINSULA TODAY AND TONIGHT AS ANOTHER UPPER LOW DIGS INTO THE
MID MS RIVER VALLEY. THIS UPPER LOW BECOMES CUT OFF FROM THE UPPER
FLOW AND MEANDERS NORTHWARD AND WEAKENS OVER THE UPPER MIDWEST MON.
A LONG WAVE RIDGE DEVELOPS AND EXTENDS FROM THE GULF OF MEX TO N OF
THE GREAT LAKES TUE...MOVING E TO NEW ENGLAND WITH A CLOSED UPPER
LOW FORMING OVER THE MID ATLC STATES WED AND THU.
FOR THE SHORT TERM...TODAY THROUGH SUN...ATMOSPHERE A BIT DRIER BUT
SCATTERED POPS STILL EXPECTED...MAINLY ALONG THE E COAST THIS
MORNING AND IN THE INTERIOR AND W THIS AFTERNOON. SOME E COAST
NOCTURNAL SHOWERS TONIGHT. RIDGE OVER THE AREA SAT INTO SUN PUTS A
DRY MID LEVEL CAPPING LAYER OVER S FLA AND POPS AGAIN A BIT LOWER.
EXTENDED PERIOD...MON THROUGH THU...GRADUAL MOISTENING THE
ATMOSPHERE OCCURS AS A WEAK SURFACE TROUGH CURRENTLY OVER THE
BAHAMAS MOVES OVER S FLA. SCATTERED POPS EXPECTED WITH NEAR NORM
TEMPS.
MARINE...WINDS NE 10 TO 15 KNOTS TODAY DUE TO LOW PRES DEVELOPING
WELL OFF OF THE COAST E OF JAX. WINDS BECOME E TONIGHT INTO THE
WEEKEND AND DECREASE TO 10 KNOTS. WINDS BACK TO 10 TO 15 KNOTS NEXT
WEEK. GULF STREAM SEAS TO 5 FEET TODAY BUT BECOMING 4 FEET OR LESS
THE REMAINDER OF THE PERIOD. AT TIMES EARLY NEXT WEEK.
FIRE WEATHER...MINIMUM RH ABOVE CRITICAL VALUES THROUGH THE PERIOD.
NO PROBLEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 76 89 76 / 40 20 30 30
FORT LAUDERDALE 90 78 88 78 / 40 20 30 30
MIAMI 90 77 89 77 / 40 20 30 30
NAPLES 91 74 90 73 / 30 10 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...18/GR
SHORT TERM/AVIATION...30/KOB
000
FXUS62 KTBW 191330
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
930 AM EDT FRI SEP 19 2008
.UPDATE...DEEP NORTH TO NORTHEAST FLOW HAS BROUGHT A DRIER AIRMASS
INTO THE REGION WITH MORNING TBW AND CAPE CANAVERAL SOUNDINGS
INDICATING PRECIPITABLE WATER AROUND 1.4 INCHES. WEST COAST SEA
BREEZE WILL BE PRETTY MUCH NONE EXISTENT AS NORTHEAST LOW LEVEL FLOW
REMAINS BETWEEN 10 AND 15 KNOTS AND WITH THE DRIER AIR IN PLACE
CHANCE OF SEEING PRECIPITATION LOOKS PRETTY LIMITED. BEST CHANCE
OF SEEING A SHOWER OR THUNDERSTORM WILL BE OVER THE SOUTHERN INTERIOR
AND SOUTHWEST COUNTIES DURING THE LATE AFTERNOON...OTHERWISE LOOKS
LIKE A MOSTLY SUNNY AND DRY DAY. OVERALL THE CURRENT ZONE FORECAST
LOOKS ON TRACK AND WILL ONLY UPDATE TO REMOVE PATCHY FOG FROM THIS
MORNING.
&&
.MARINE...BREEZY NORTHEAST FLOW ACROSS THE COASTAL WATERS THIS
MORNING WITH EXERCISE CAUTION CRITERIA ONGOING ACROSS THE NORTHERN
AND CENTRAL WATERS...AS WELL AS LOWER AND MIDDLE TAMPA BAY. WINDS
SHOULD DIMINISH SOME THIS AFTERNOON THEN INCREASE ONCE AGAIN THIS
EVENING AND OVERNIGHT. PRESENT MARINE FORECAST LOOKS ON OK...BUT
WILL ADD EXERCISE CAUTION FOR CENTRAL NEAR SHORE WATERS AND TAMPA
BAY INTO EARLY THIS AFTERNOON...OTHERWISE NO MAJOR CHANGES ARE
PLANNED FOR LATE MORNING FORECAST.
&&
.AVIATION...VFR EXPECTED TO PREVAIL TODAY AT ALL TAF SITES WITH
BRIEF PERIODS OF CLOUD LAYERS IN THE MVFR RANGE LATER IN THE
AFTERNOON. FMY AND RSW MAY ALSO EXPERIENCE PERIODS OF WINDS IN THE
12 TO 15 KNOT RANGE WITH GUSTS AROUND 20 KNOTS THIS AFTERNOON.
THEN VFR WITH LIGHTER WINDS SHOULD PREVAIL LATER IN THE EVENING AND
OVERNIGHT AT ALL TAF SITES.
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/MARINE...PRC
AVIATION...AR
000
FXUS62 KTAE 191312
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
910 AM EDT FRI SEP 19 2008
.UPDATE...GOES WATER VAPOR ANIMATION DEPICTED AN ACTIVE NRN STREAM
ACROSS SRN CANADA. FURTHER SOUTH, TROUGHS WERE POSITIONED OFF THE CA
COAST, OVER THE PLAINS STATES AND OFF THE SRN ATLANTIC COAST, WITH
RIDGES OVER THE INTERMTN WEST AND FROM THE SERN STATES TO SRN GREAT
LAKES. A STRONG SURFACE RIDGE CENTERED OVER NEW ENGLAND RIDGED SWWD
INTO THE SERN STATES. LOW PRESSURE WAS DEEPENING NE OF THE BAHAMAS.
THE TIGHT GRADIENT BETWEEN THESE FEATURES HAS INCREASED THE E-NE
WINDS OVER THE MARINE AREA. LOW LEVEL CONVERGENCE, ASSOCIATED WITH
REMNANT E COAST SEA BREEZE, TRIGGERED ISOLD SHRA/TS OVER THE NERN
GULF WATERS. THIS ACTIVITY HAS PUSHED WWD INTO THE OFFSHORE
PANHANDLE LEGS. OTHERWISE, SKIES WERE M/SUNNY. MODERATE ELY FLOW IN
THE LOW LEVELS BACKED TO THE N AND NW IN THE MID/UPPER LEVELS. SOME
OF THE DRY AIR ALOFT HAS PENETRATED INTO THE LOWER LEVELS. WITH
VERTICAL MIXING DURING THE AFTN, THIS DRY AIR WILL PUSH RH VALUES
BELOW 40 PERCENT OVER INLAND AREAS. WITH THE MODERATE ELY 1000-700
MB FLOW, CONVECTION THAT DEVELOPS WILL BE ISOLD AND RELEGATED TO THE
PANHANDLE ZONES. OVERALL, THE ZONE FCST PACKAGE APPEARS ON TRACK,
AND WILL UPDATE TO REMOVE MORNING WORDING.
&&
.AVIATION...LOW CLOUDS HAVE NOT MATERIALIZED LIKE THE LAST FEW
MORNINGS ACROSS THE AREA. KDHN HAS MVFR VSBY CURRENTLY BUT THIS
SHOULD BURN OFF VERY QUICKLY WITH VFR CONDITIONS PREVAILING.
&&
.MARINE...THE ELY SURGE THAT DEVELOPED OVERNIGHT PEAKED AROUND
SUNRISE, AND HAS BEGUN TO EBB. SEAS WERE RUNNING 6 FT AT THE BUOYS,
AND WINDS HAVE DIMINISHED TO 15-20 KTS. BASED ON THESE TRENDS, WILL
LET THE SCA FOR THE OFFSHORE LEGS EXPIRE AT 14Z, AND REPLACE THE
HEADLINE WITH AN SCEC. ALSO, WILL DROP THE NEARSHORE LEGS HEADLINE
ON THE MORNING FCST UPDATE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 88 65 85 66 / 05 05 20 10
PANAMA CITY 87 66 84 67 / 20 20 30 30
DOTHAN 84 62 81 62 / 10 05 20 20
ALBANY 86 62 83 63 / 0 05 20 20
VALDOSTA 87 63 83 65 / 0 05 20 20
CROSS CITY 88 66 86 67 / 10 05 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...SCA OFFSHORE LEGS UNTIL 10 AM EDT.
&&
$$
JAMSKI/CAMP
000
FXUS62 KMFL 191123
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
723 AM EDT FRI SEP 19 2008
.AVIATION...
MOSTLY VFR CONDITIONS ARE ANTICIPATED ACROSS S FLA THROUGH THE
NEXT 24 HOURS. A QUICK PASSING SHRA MAY BE POSSIBLE ALONG THE E
CST THIS MORNING BUT ANY LOWERING OF CIG/VSBY TO MVFR WILL ONLY BE
FOR LESS THAN 15 MINUTES. SCT TSRA WILL DEVELOP AFT 14Z WITH LOW
LEVEL NE FLOW STEERING CONVECTION INLAND AWAY FROM THE E CST AND
HAVE ONLY PLACED VCTS IN THE TAFS. THE THREAT REMAINS LOW ENOUGH
EVEN THOUGH SOME OF THE STORMS WILL MOVE TO THE SW CST HAVE ONLY
PLACED VCSH IN THE TAF FOR KAPF. THE NE FLOW WILL PICK UP TO
AROUND 12KT ALONG THE E CST AFT 13Z AND THIS WILL PREVENT A W CST
SEA BREEZE FROM DEVELOPING.
30/KOB
&&
.PREV DISCUSSION... /ISSUED 311 AM EDT FRI SEP 19 2008/
DISCUSSION...THE UNSEASONABLE DEEP UPPER TROUGH ALONG THE U.S. E
SEA BOARD HAS MOVED E INTO THE ATLC. A SHORT WAVE RIDGE EXTENDING
FROM THE NE GULF OF MEX N INTO THE OH RIVER VALLEY MOVES E OVER THE
FLA PENINSULA TODAY AND TONIGHT AS ANOTHER UPPER LOW DIGS INTO THE
MID MS RIVER VALLEY. THIS UPPER LOW BECOMES CUT OFF FROM THE UPPER
FLOW AND MEANDERS NORTHWARD AND WEAKENS OVER THE UPPER MIDWEST MON.
A LONG WAVE RIDGE DEVELOPS AND EXTENDS FROM THE GULF OF MEX TO N OF
THE GREAT LAKES TUE...MOVING E TO NEW ENGLAND WITH A CLOSED UPPER
LOW FORMING OVER THE MID ATLC STATES WED AND THU.
FOR THE SHORT TERM...TODAY THROUGH SUN...ATMOSPHERE A BIT DRIER BUT
SCATTERED POPS STILL EXPECTED...MAINLY ALONG THE E COAST THIS
MORNING AND IN THE INTERIOR AND W THIS AFTERNOON. SOME E COAST
NOCTURNAL SHOWERS TONIGHT. RIDGE OVER THE AREA SAT INTO SUN PUTS A
DRY MID LEVEL CAPPING LAYER OVER S FLA AND POPS AGAIN A BIT LOWER.
EXTENDED PERIOD...MON THROUGH THU...GRADUAL MOISTENING THE
ATMOSPHERE OCCURS AS A WEAK SURFACE TROUGH CURRENTLY OVER THE
BAHAMAS MOVES OVER S FLA. SCATTERED POPS EXPECTED WITH NEAR NORM
TEMPS.
MARINE...WINDS NE 10 TO 15 KNOTS TODAY DUE TO LOW PRES DEVELOPING
WELL OFF OF THE COAST E OF JAX. WINDS BECOME E TONIGHT INTO THE
WEEKEND AND DECREASE TO 10 KNOTS. WINDS BACK TO 10 TO 15 KNOTS NEXT
WEEK. GULF STREAM SEAS TO 5 FEET TODAY BUT BECOMING 4 FEET OR LESS
THE REMAINDER OF THE PERIOD. AT TIMES EARLY NEXT WEEK.
FIRE WEATHER...MINIMUM RH ABOVE CRITICAL VALUES THROUGH THE PERIOD.
NO PROBLEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 76 89 76 / 40 20 30 30
FORT LAUDERDALE 90 78 88 78 / 40 20 30 30
MIAMI 90 77 89 77 / 40 20 30 30
NAPLES 91 74 90 73 / 40 10 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
000
FXUS62 KMLB 190847
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
440 AM EDT FRI SEP 19 2008
.DISCUSSION...
...NE SWELLS AND INCREASING THREAT FOR RIP CURRENTS EXPECTED AT THE
BEACHES THIS WEEKEND...
TODAY-TONIGHT...WATER VAPOR IMAGERY SHOWS MUCH DRIER AIR ALOFT OVER
THE NORTHERN TWO THIRDS OF THE PENINSULA EARLY THIS MORNING. AN
UPPER TROUGH AXIS REMAINS SITUATED JUST OFFSHORE AND THIS FEATURE
WILL MAKE LITTLE PROGRESS EASTWARD DURING THE DAY. TO THE WEST WEAK
SHORTWAVE RIDGING WILL BUILD IN OVER THE PENINSULA. SURFACE HIGH
PRESSURE SITUATED ALONG THE EASTERN SEABOARD WILL KEEP GUSTY
NORTHEAST FLOW ACROSS THE AREA. DESPITE COOLER TEMPERATURES ALOFT
(-8C) SHORT TERM MODELS CONTINUE TO KEEP POPS LOW TODAY SO WILL
LOWER OUR CURRENT GRIDS TO SCHC/LOW END CHC...WITH HIGHEST POPS
(30%) SITUATED SOUTHWARD WHERE GREATEST DEEP LAYER MOISTURE WILL
RESIDE ALONG WITH WHAT IS LEFT OF THE DIFFUSE FRONTAL BOUNDARY FROM
PREVIOUS DAYS. WILL KEEP A SMALL CHANCE FOR PCPN ALONG THE COAST
OVERNIGHT. MARINE INFLUENCE WILL KEEP TEMPERATURES AROUND THE MIDDLE
80S ALONG THE COAST WITH A FEW UPPER 80S EXPECTED FOR HIGHS FARTHER
INLAND. LOWS IN THE LOWER 70S WITH A FEW M70S ALONG THE IMMEDIATE
COAST.
SAT-MON...WHILE FEATURES TO THE NORTH OF FL PROGRESS...THE PATTERN
INVOF FL REMAINS RATHER STAGNANT. THE SHORT WAVE TROUGH OFFSHORE
THE EAST COAST OF FL WILL MINOR OUT EARLY SAT AS WRN ATLC DLM RIDGE
BUILDS WWD INTO THE BAHAMAS. FROM THE WEEKEND INTO MON...THE CTRL
CONUS SHORT WAVE TROUGH WILL SLIDE EAST AND THEN START TO DAMPEN
OUT AS IT MOVES INTO CONFLUENT UPPER FLOW BTWN IT AND A STRONGER
NRN STREAM TROUGH MOVING EWD OVER THE NERN CONUS/SE CANADA. NET
RESULT WILL BE THAT THE STALLED FRONTAL BDRY JUST OFFSHORE THE SERN
SEABOARD WILL REMAIN QSTNRY AS WEAK LOW PRES WAVES RIPPLE NEWD ALONG
IT THRU SUN...WITH THE LOCAL PGRAD WEAKENING SLIGHTLY AS THE HIGH TO
THE NORTH SLOWLY FILLS. A STRONGER SFC HIGH WILL BUILD SWD ACROSS
THE ERN CONUS/WRN ATLC...BRIDGING THE QSTNRY BDRY AND RESTRENGTHENING
THE LOCAL ONSHORE FLOW.
WITH THE MID/UPR TROUGH LINGERING TO THE NW...ECFL WILL BE IN A
RELATIVELY POSITIVE JET FORCED ASCENT REGIME. COUPLED WITH POOLED
DEEP LYR MOISTURE INVOF THE STALLED FRONT...EXPECT SKIES TO REMAIN
ON THE MCLDY SIDE MUCH OF THE SHORT RANGE. WAS TEMPTED TO TRIM BACK
EXTENT OF TS TO ISOLD WHILE KEEPING POPS IN THE SCT RANGE (HIGHEST
SUN/MON) BUT TO KEEP AREAL CONTINUITY WILL LEAVE WELL ENOUGH ALONE.
TUE-FRI...SHARP AMPLITUDE SHORT WAVE RIDGE BUILDS IN BEHIND THE
DEPARTING NRN STREAM TROUGH. THIS TRAPS THE VORT ENERGY FROM THE
CTRL-ERN CONUS TROUGH AND CAUSES IT TO DRIFT SWD EITHER NEAR OR
OFFSHORE THE NC OUTER BANKS THRU THU...BEFORE STARTING TO LIFT BACK
NWD ON FRI. 00Z ECM IS STRONGER THAN THE GFS WITH BOTH THE H50 LOW
AS WELL AS THE SFC LOW WHICH SPINS UP ALONG THE STALLED FRONT. ECM
SOLN MIGHT PORTEND SOME DRIER AIR TRYING TO WRAP AROUND THE BACKSIDE
OF THE LOW AND INTO FL...WHILE THE FAVORED GFS SOLN IS WEAKER WITH
THE LOW AND KEEPS ECFL IN HIGHER MEAN MOISTURE. WILL CONTINUE TREND
OF MID-HIGH END SCT POPS IN A PERSISTENT MOIST ONSHORE FLOW REGIME.
AS WITH THE SHORT RANGE...THINK PROSPECTS FOR TS WILL BE RATHER
LIMITED GIVEN THE MAGNITUDE OF THE ONSHORE FLOW COUPLED WITH EXTENT
OF CLOUD COVER.
&&
.AVIATION...PREVAILING VFR CONDITIONS. BRIEF IFR CIGS/VSBYS FROM
KMLB SOUTHWARD THIS MORNING FROM ATLC SHRA`S MOVING ONSHORE. ISOLD
TO WDLY SCT SHRA/TSRA ACTIVITY POSSIBLE NEAR TERMINAL AERODROMES
THIS AFTN. BREEZY CONDITIONS DVLPNG WITH NORTHEAST WINDS GUSTING 20+
KTS EXPECTED.
&&
.MARINE...TODAY/TONIGHT...NORTHEAST WINDS 15-20 KTS TO CONTINUE INTO
THIS AFTN FROM FLAGLER BEACH-SEBASTIAN INLET 20NM TO 60NM. SEAS NEAR
6 FT AT BUOY 41009. CONDITIONS FOR SMALL CRAFT WILL REMAIN POOR
TODAY AS A NORTHEAST SWELL CONTINUES TO BUILD OVER THE COASTAL
WATERS. WILL GO WITH STRONGLY WORDED CAUTIONARY STATEMENT FOR
OFFSHORE LEGS NORTH OF SEBASTIAN INLET. NORTHEAST WINDS EXPECTED TO
FALL OFF THIS EVENING SLIGHTLY...BUT SEAS AWAY FROM THE COAST WILL
REMAIN ELEVATED DUE TO THE SWELL. EXPECT NE SWELL TO LINGER
THROUGHOUT THE WEEKEND...THOUGH HAVE TRIMMED BACK COMBINED SEAS TO
5-6FT AS THE DIRECT FETCH APPEARS TO BE DIRECTED MORE TWD NC/SC/GA
AND NORTH FL. WILL LKLY NEED CAUTIONARY STMT FOR SEAS DURING MUCH
OF THE UPCOMING WEEKEND...WITH SWELL PSBL WEAKENING A TAD LATE SUN.
EXPECT COMBINATION OF MDT WIND CHOP AND BACKGROUND SWELL TO KEEP
SEAS IN THE 4-5FT RANGE MON/TUE...THOUGH THIS WILL BECOME DEPENDENT
UPON HOW MUCH OF LOW SPINS UP OFF THE CAROLINAS. WX REGIME LOOKS
UNSETTLED THROUGHOUT WITH SCT SHRA/TS THROUGH MOST OF THE FCST PD.
THERE REMAINS AN ENHANCES POTENTIAL FOR RIP CURRENTS THIS WEEKEND.
PERSISTENT SWELL/ONSHORE FLOW WILL PILE UP WATER SHOREWARD OF THE
SAND BAR...WITH FREQUENT BREACHES FORMING IN IT AS WATER RETREATS
SEAWARD.
&&
.HYDROLOGY...SLOW FALL TO CONTINUE OVER THE MIDDLE ST JOHNS RIVER
BASIN THRU EARLY NEXT WEEK...ALTHOUGH ALL FORECAST POINTS WILL
CONTINUE ABOVE FLOOD STAGE. FOR THE LATEST INFO ON ST JOHNS RIVER
LEVEL SEE THE RIVER FLOOD STATEMENT /MIAFLSMLB/.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 85 71 83 72 / 20 20 40 20
MCO 88 71 86 71 / 20 10 30 20
MLB 85 71 85 71 / 30 20 40 20
VRB 86 72 87 72 / 30 20 40 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...SEDLOCK
LONG TERM....CRISTALDI
000
FXUS62 KJAX 190753
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
353 AM EDT FRI SEP 19 2008
.SHORT TERM...TODAY THROUGH SUNDAY...
HIGH PRESSURE RIDGE HAS BUILT DOWN THE EAST COAST WITH AN INVERTED
TROF WELL OFFSHORE. NORTHEAST FLOW HAS BECOME ESTABLISHED ACROSS THE
REGION AND WILL CONTINUE THROUGH THE WEEKEND. ABUNDANT DRY AIR IN
THE MID/UPPER LEVELS HAS OVERSPREAD THE REGION AND WILL BE SLOW TO
MOISTEN OVER THE WEEKEND AND THIS WILL LEAD TO ONLY ISOLD SHOWER
ACTIVITY ALONG THE COASTAL AREAS TODAY...WITH AN INCREASE TO SCTD
SHOWERS AND ISOLD TSTMS ON SATURDAY THEN SCTD TO NUMEROUS COVERAGE
ON SUNDAY. HAVE ISSUED LAKE WIND ADVISORY FOR THE COASTAL COUNTIES
INCLUDING CLAY AND PUTNAM ALONG THE ST JOHNS RIVER AS SUSTAINED
NORTHEAST WINDS INCREASE TO AROUND 20 MPH WITH GUSTS UP TO 30 MPH AT
TIMES. MAX TEMPS WILL REMAIN SLIGHTLY BELOW NORMAL IN THE LOWER TO
MID 80S THROUGH THE WEEKEND.
.LONG TERM...MONDAY THROUGH THURSDAY...
INVERTED TROF SETTING UP OVER THE WRN ATLC JUST EAST OF THE REGION
AND THIS INCREASED MOIST NORTHEAST FLOW IN CONJUNCTION WITH
SUBTROPICAL JET ALOFT WILL SET THE STAGE FOR LOCALLY HEAVY RAINFALL
FROM CONVERGENT RAIN BANDS SETTING UP ALONG THE COASTAL AREAS.
HAVE CAPPED POPS AT 50% FOR NOW IN THE EXTENDED TIME FRAME BUT WILL
LIKELY NEED TO GO HIGHER AS FORECAST COMES CLOSER. 00Z GFS ENSEMBLE
RUNS STILL SUPPORTING 7 DAY RAINFALL TOTALS OF 2 TO 4 INCHES ALONG
THE COASTAL COUNTIES AND 1 TO 2 INCHES MUCH FURTHER INLAND.
&&
.AVIATION...DEW PT DEPRESSIONS ARE FALLING WITHIN 3-4 DEG AS TEMPS
FALL INTO THE UPPER 60S WITH DEW PTS IN THE LOWER 60S. BELIEVE THAT
ENOUGH TURBULENT MIXING SHOULD PREVENT SIGNIFICANT FG DEVELOPMENT
NEAR THE COAST THIS MORNING...BUT ENOUGH DECOUPLING SHOULD OCCUR AT
JAX AND GNV FOR MVFR TO POSSIBLE LIFR FOR A BRIEF DURATION BEFORE
SUNRISE. WINDS WILL INCREASE TO SUSTAINED 15-20 KTS WITH GUSTS TO 25
KTS TODAY.
&&
.MARINE...SCA IN EFFECT FOR ALL LEGS TODAY PERSISTING INTO EARLY
EVENING FOR THE NEARSHORE WATERS AND LATE SAT FOR THE OFFSHORE LEGS.
ONSHORE FLOW WILL PERSIST THROUGH THE WEEKEND AND EARLY NEXT WEEK
WHICH WILL CONTINUE AN ELEVATED RIP CURRENT RISK AND AT LEAST SCEC
CONDITIONS FOR MUCH OF THE PERIOD FOR OUR OFFSHORE LEGS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 84 61 81 61 / 0 0 10 0
SSI 81 69 79 70 / 10 30 30 20
JAX 83 67 81 66 / 10 20 40 20
SGJ 82 72 81 71 / 20 20 40 30
GNV 85 66 84 65 / 20 0 30 10
OCF 86 66 85 66 / 20 0 30 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY FROM 9 AM THIS MORNING TO 7 PM EDT THIS
EVENING FOR CLAY-DUVAL-FLAGLER-NASSAU-PUTNAM-ST JOHNS.
GA...LAKE WIND ADVISORY FROM 9 AM THIS MORNING TO 7 PM EDT THIS
EVENING FOR COASTAL CAMDEN-COASTAL GLYNN-INLAND CAMDEN-
INLAND GLYNN.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE-
FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE-
ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR ALTAMAHA SOUND
GA TO FERNANDINA BEACH FL OUT 20 NM-FERNANDINA BEACH TO ST
AUGUSTINE FL OUT 20 NM-ST AUGUSTINE TO FLAGLER BEACH FL OUT
20 NM.
&&
$$
HESS/ENYEDI
000
FXUS62 KKEY 190751
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
351 AM EDT FRI SEP 19 2008
.DISCUSSION...
.CURRENTLY...
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ACROSS THE
FORECAST AREA EARLY THIS MORNING...WITH MOST OF THE ACTIVITY SOUTH OF
A LINE FROM CAPE SABLE TO THE DRY TORTUGAS. SEVERAL OLD OUTFLOW
BOUNDARIES ARE PRESENT ACROSS THE KEYS AND ADJACENT COASTAL
WATERS...AND ARE SERVING TO FOCUS CONVECTIVE ACTIVITY. SKIES ARE
PARTLY TO MOSTLY CLOUDY ALONG THE KEYS ISLAND CHAIN...WITH
TEMPERATURES AROUND 80 DEGREES. WINDS ARE FROM THE NORTHEAST TO EAST
NEAR 10 KNOTS ON LAND...AND NEAR 15 KNOTS ALONG THE REEF.
SURFACE ANALYSIS DEPICTS A STATIONARY FRONT LYING ACROSS THE FLORIDA
PENINSULA NEAR LAKE OKEECHOBEE AND EXTENDING NORTHEAST INTO THE
ATLANTIC OCEAN...WITH A SPRAWLING HIGH PRESSURE AREA COVERING THE
ENTIRE EASTERN SEABOARD NORTH OF THE FRONT...AND WEDGING DOWN THE
FLORIDA PENINSULA. AT MID AND UPPER LEVELS...BROAD CYCLONIC FLOW
ASSOCIATED WITH A DEEP LAYER TROUGH IS PRESENT ACROSS EASTERN FLORIDA
AND THE ADJACENT ATLANTIC WATERS...WITH A SHORTWAVE TROUGH EVIDENT
ON WATER VAPOR IMAGERY MOVING OFFSHORE FROM EAST CENTRAL FLORIDA. A
MOIST AND UNSTABLE AIRMASS REMAINS IN PLACE ACROSS SOUTH FLORIDA AND
THE KEYS...WHILE WATER VAPOR IMAGERY AND EVENING SOUNDINGS REVEAL A
SIGNIFICANTLY DRIER AIRMASS PRESENT ACROSS CENTRAL AND NORTH FLORIDA.
.SHORT TERM (TODAY THROUGH SUNDAY)...
THE MID AND UPPER LEVEL TROUGH IS EXPECTED TO MOVE SLOWLY EASTWARD
OFF THE FLORIDA COAST TODAY...WITH WEAK ANTICYCLONIC FLOW BUILDING
INTO THE STATE. AT LOWER LEVELS...THE DRY AIR PRESENT TO OUR NORTH IS
FORECAST TO SLOWLY FILTER SOUTHWARD DURING THE NEXT 24 HOURS...WITH
MODEL DEPICTED PRECIPITABLE WATER VALUES DROPPING TO NEAR 1.5 INCHES
BY EARLY SATURDAY MORNING. THESE FACTORS SHOULD LEAD TO A GRADUALLY
LESS FAVORABLE LARGE SCALE ENVIRONMENT FOR PRECIPITATION THROUGH
SATURDAY MORNING. HOWEVER...AT SMALLER SCALES...MODEL SOUNDINGS
DEPICT A FAVORABLE WIND PROFILE AND SUFFICIENT LOW LEVEL MOISTURE FOR
A PRECIPITATING CLOUD LINE ONCE AGAIN TODAY...AS WE HAVE SEEN FOR THE
PAST COUPLE OF DAYS. NORTHEAST STEERING FLOW SHOULD ALSO ALLOW FOR
MAINLAND CONVECTION TO MOVE DOWN INTO OUR AREA DURING THE AFTERNOON
AND EVENING HOURS. THEREFORE...WILL MAINTAIN 40 PERCENT POPS FOR
TODAY AND TONIGHT.
SATURDAY THROUGH SUNDAY...A RATHER BLAND SURFACE AND UPPER AIR PATTERN
IS FORECAST TO BE IN PLACE ACROSS THE REGION DURING THIS TIME...WITH
WEAK LOW PRESSURE OFF THE SOUTHEASTERN U.S. COAST RESULTING IN A
WEAKER RIDGE TO OUR NORTH...AND THE FIRST UPPER LEVEL TROUGH WASHING
OUT TO OUR EAST WHILE ANOTHER ONE DEVELOPS ACROSS THE NORTH CENTRAL
GULF OF MEXICO. WEAK TROPICAL WAVE ACTIVITY ACROSS THE CARIBBEAN SEA
SHOULD REMAIN TO OUR SOUTH WITH LITTLE OR NO EFFECT ON OUR WEATHER. A
SOMEWHAT DRIER AIRMASS MAY BE PRESENT ACROSS THE AREA AT LEAST FOR
SATURDAY. IN ANY CASE...WE SHOULD STILL HAVE SUFFICIENT LOW LEVEL
MOISTURE...ALONG WITH A LACK OF SUPPRESSING MID LEVEL SUBSIDENCE (DUE
TO THE ABSENCE OF A STRONG ATLANTIC SUBTROPICAL RIDGE ALOFT)...TO
SUPPORT LOW END CHANCE POPS OF 30 PERCENT FOR EACH PERIOD. THIS IS
SLIGHTLY ABOVE THE MODEL GENERATED MOS POPS...BUT IS CLOSE TO
CLIMATOLOGY AS WE ARE NEAR THE PEAK OF THE WET SEASON.
.LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
ABUNDANT ATMOSPHERIC MOISTURE AND THE LACK OF A DOMINANT ATLANTIC
SUBTROPICAL RIDGE ACROSS FLORIDA SHOULD CHARACTERIZE THE LONG TERM
PERIOD. GLOBAL MODELS DISAGREE AS TO THE DETAILS...BUT ALL DO DEVELOP
A SIGNIFICANT MID/UPPER LEVEL TROUGH SOMEWHERE NEAR THE MID ATLANTIC
REGION...KEEPING THE RIDGE AT BAY. THE KEYS REMAIN WITHIN GENERALLY
EASTERLY FLOW AT THE SURFACE...WITH MOISTURE LIKELY SUFFICIENT FOR
CONVECTIVE PRODUCTION. THIS LARGE SCALE ENVIRONMENT SHOULD BE
FAVORABLE FOR MESOSCALE INTERACTIONS SUCH AS CLOUD LINES...OUTFLOW
BOUNDARIES AND MAINLAND EFFECTS EACH DAY. WILL MAINTAIN NEAR CLIMO
POPS OF 30 PERCENT AND NORMAL TEMPS THROUGHOUT THE LONG TERM PERIOD.
&&
.MARINE...
MODERATE NORTHEAST TO EAST BREEZES HAVE PREVAILED ACROSS THE KEYS
COASTAL WATERS DURING MUCH OF THE NIGHT. EXPECT SIMILAR CONDITIONS TO
CONTINUE TODAY AND INTO TONIGHT AS A RATHER STRONG HIGH PRESSURE AREA
REMAINS PARKED ALONG THE EAST COAST AND WEDGES DOWN INTO FLORIDA...
KEEPING US IN A RELATIVELY TIGHT PRESSURE GRADIENT. WINDS AND SEAS
WILL BE HIGHER ONCE AGAIN NEAR SCATTERED SHOWERS AND THUNDERSTORMS
TODAY AND THIS EVENING. EASTERLY FLOW SHOULD WEAKEN SLIGHTLY LATE
TONIGHT THROUGH SUNDAY...AS A WEAK LOW PRESSURE AREA DEVELOPS OFF THE
SOUTHEASTERN U.S. COAST AND WEAKENS THE HIGH PRESSURE RIDGE. HIGH
PRESSURE IS FORECAST TO STRENGTHEN ONCE AGAIN TO OUR NORTH EARLY
NEXT WEEK...WHICH SHOULD LEAD TO INCREASING EASTERLY FLOW ONCE AGAIN.
AT THIS POINT...NO ADVISORIES OR CAUTIONARY STATEMENTS ARE
ANTICIPATED ACROSS THE COASTAL WATERS THROUGH TUESDAY...BUT WINDS
NEAR 15 KNOTS ARE POSSIBLE OVER THE ATLANTIC WATERS THROUGH TONIGHT...
AND AGAIN MONDAY AND TUESDAY.
&&
.AVIATION...
A BRIEF ROUND OR TWO OF MVFR/IFR CONDITIONS ARE POSSIBLE AT THE
ISLAND TERMINALS OVERNIGHT...AS SCATTERED SHOWERS WITH A FEW
EMBEDDED THUNDERSTORMS TRACK WEST-SOUTHWESTWARD AT AROUND 15 KNOTS
THROUGH THE WATERS SURROUNDING THE FLORIDA KEYS. ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS MAY PASS NEAR EITHER TERMINAL BUT MORE
LIKELY NEAR THE KEYW TERMINAL BETWEEN 18 AND 22Z...ACCOMPANIED BY
BRIEF MVFR/IFR CEILINGS AND VISIBILITIES. SURFACE WINDS WILL BE OUT
OF THE EAST NORTHEAST AT 5 TO 10 KNOTS WITH GUSTS TO 15 TO 20 KNOTS
NEAR SHOWERS AND THUNDERSTORMS THAT MAY OCCUR.
&&
.PRELIMINARY POINT TEMPS/POPS...
KEY WEST 87 79 88 79 / 40 40 30 30
MARATHON 88 79 89 79 / 40 40 30 30
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........JACOBSON
AVIATION/NOWCASTS.....BWC
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KMFL 190711
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
311 AM EDT FRI SEP 19 2008
CURRENTLY 88-D LOOPS INDICATES WIDELY SCATTERED SHOWERS MOVING WSW
FROM THE ATLC TOWARD S FLA WITH SOME OF THE ACTIVITY MOVING ONTO
PALM BEACH COUNTY AND EXTENDING IN TO THE W INTERIOR.
.DISCUSSION...THE UNSEASONABLE DEEP UPPER TROUGH ALONG THE U.S. E
SEA BOARD HAS MOVED E INTO THE ATLC. A SHORT WAVE RIDGE EXTENDING
FROM THE NE GULF OF MEX N INTO THE OH RIVER VALLEY MOVES E OVER THE
FLA PENINSULA TODAY AND TONIGHT AS ANOTHER UPPER LOW DIGS INTO THE
MID MS RIVER VALLEY. THIS UPPER LOW BECOMES CUT OFF FROM THE UPPER
FLOW AND MEANDERS NORTHWARD AND WEAKENS OVER THE UPPER MIDWEST MON.
A LONG WAVE RIDGE DEVELOPS AND EXTENDS FROM THE GULF OF MEX TO N OF
THE GREAT LAKES TUE...MOVING E TO NEW ENGLAND WITH A CLOSED UPPER
LOW FORMING OVER THE MID ATLC STATES WED AND THU.
FOR THE SHORT TERM...TODAY THROUGH SUN...ATMOSPHERE A BIT DRIER BUT
SCATTERED POPS STILL EXPECTED...MAINLY ALONG THE E COAST THIS
MORNING AND IN THE INTERIOR AND W THIS AFTERNOON. SOME E COAST
NOCTURNAL SHOWERS TONIGHT. RIDGE OVER THE AREA SAT INTO SUN PUTS A
DRY MID LEVEL CAPPING LAYER OVER S FLA AND POPS AGAIN A BIT LOWER.
.EXTENDED PERIOD...MON THROUGH THU...GRADUAL MOISTENING THE
ATMOSPHERE OCCURS AS A WEAK SURFACE TROUGH CURRENTLY OVER THE
BAHAMAS MOVES OVER S FLA. SCATTERED POPS EXPECTED WITH NEAR NORM
TEMPS.
&&
.MARINE...WINDS NE 10 TO 15 KNOTS TODAY DUE TO LOW PRES DEVELOPING
WELL OFF OF THE COAST E OF JAX. WINDS BECOME E TONIGHT INTO THE
WEEKEND AND DECREASE TO 10 KNOTS. WINDS BACK TO 10 TO 15 KNOTS NEXT
WEEK. GULF STREAM SEAS TO 5 FEET TODAY BUT BECOMING 4 FEET OR LESS
THE REMAINDER OF THE PERIOD. AT TIMES EARLY NEXT WEEK.
&&
.FIRE WEATHER...MINIMUM RH ABOVE CRITICAL VALUES THROUGH THE PERIOD.
NO PROBLEMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 75 89 76 / 40 20 30 30
FORT LAUDERDALE 89 78 88 77 / 40 20 30 30
MIAMI 90 77 89 77 / 40 20 30 30
NAPLES 91 74 90 73 / 40 10 30 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...15/JR
SHORT TERM/AVIATION...04/AT
000
FXUS62 KTAE 190639 CCA
AFDTAE
AREA FORECAST DISCUSSION...
NATIONAL WEATHER SERVICE TALLAHASSEE FL
230 AM EDT FRI SEP 19 2008
.SYNOPSIS....
AT 2 AM EDT...SKIES RANGED FROM FAIR TO M/CLDY WITH MID LEVEL CIGS.
COMBINATION OF LOW LEVEL NE FLOW TAPPING ATLC MOISTURE AND UPPER
LEVEL NW FLOW HELPED SUSTAIN COASTAL AND MARINE CONVECTION LATE
THURS NIGHT INTO PREDAWN HOURS OF FRI. UNDER NE LOW LEVEL
FLOW...CONVECTION WILL SLOWLY MOVE AWAY FROM COAST AND NEARSHORE
WATERS. 24 HR TEMP/DEW POINT COMPARISON SHOWS THAT LOCAL AIRMASS A
LITTLE WARMER AND MOISTER WES OF THE APALACHICOLA...BUT A LITTLE
DRIER AND COOLER EAST OF RIVER...ESPECIALLY IN S/CNTRL GA.
AT UPPER LEVELS...
LOOKING AT THE BIG PIX...SPLIT FLOW REGIME WITH MAIN ACTIVITY IN NRN
STREAM HIGHLIGHTED AS FOLLOWS: MAIN WESTERLIES BELT REMAINS ACROSS
CANADA. MAIN U.S. FEATURES INCLUDE TROUGH/UPR LOW MOVING INTO THE
PAC NW/INTER MOUNTAIN REGION...RIDGE OVER INTERMOUNTAIN REGION...A
TROUGH OVER THE SRN PLAINS CONUS WITH A DISTURBANCE EXITING EWD
TOWARDS THE MID/LWR MS VLY REGION...A STRONG RIDGE OVER SE WITH 588
HIGH IN TENN VALLEY AND A TROUGH OVER EXTREME WRN ATLC. BY TONIGHT
...SRN PLAINS TROUGH WILL MOVE INTO CNTRL CONUS THRU TONIGHT
KICKING DOWNSTREAM RIDGE/TROUGH FURTHER EWD.
CLOSER TO HOME..H5/H2 TROUGH CONTS TO MOVE INTO WRN ATLC WITH SHORT
WAVE RIDGING IN ITS WAKE. THIS REFLECTED IN 00Z SOUNDINGS WHICH SHOW
STRONG SUBSIDENCE INVERSIONS...NW STEERING FLOW AND A VERY DRY
AIRMASS ABOVE LOWER LEVELS BUT UNDER NE FLOW...SOUNDINGS RETAIN
MOIST LOW LEVELS. FOR EXAMPLE TAE WITH INVERSION ABOVE 650 MB BUT
WITH 1.42 IN PWAT. INCREASINGLY LOWER INVERSION LEVELS AND DRY AIR
SEEN FROM E-W, I.E. BMX AND FFC WITH 1.04 IN AND 0.98 IN PWAT
RESPECTIVELY. THIS ALSO REFLECTED IN VAPOR IMAGERY THAT SHOWS A
LARGE POCKET OF MID AND UPPER LEVEL DRY AIR STRETCHING FROM
TENNESSEE TO THE CAROLINAS AND DOWN INTO FLORIDA. THE ABOVE SRN
PLAINS TROUGH WILL CONT TO MOVE EWD BUT REMAIN ANCHORED TO OUR WEST
THROUGH THE WEEKEND B4 MOVING ACROSS CWA EARLY WORK WEEK TO BE
REPLACED BY RIDGING DURING THE MIDWEEK.
AT LOWER LEVELS...
STRONG SURFACE RIDGE CENTERED OVER ACROSS NORTHERN NEW ENGLAND AND
SOUTHEASTERN CANADA OVERNIGHT BEGINNING TO NOSE DOWN THE LEE SIDE OF
THE APPALACHIANS INTO NORTH FLORIDA. A STATIONARY FRONT REMAINS
LOCATED ACROSS SOUTH CENTRAL FLORIDA. THE LOCAL AREA REMAINS BETWEEN
THESE TWO SYSTEMS WITH SLOWLY TIGHTENING GRADIENTS. LOCAL AIRMASS
WILL CONTINUE TO DRY OUT TODAY ESPECIALLY IN LOWER LEVELS. THIS
REFLECTED IN MODEL SOUNDINGS. I.E. GFS TAE WITH 1.31 IN PWAT AT 06Z
FRI LOWERING TO 0.86 IN AT 00Z SAT BEFORE A GULF LOW BEGINS TO MOVE
CLOSER TO CWA (SEE BELOW). PWATS INCREASE TO 1.65 INCH BY 12Z SUN
AND 1.78 INCH BY 00Z MON. BY SATURDAY...AN INVERTED TROUGH OFF THE
ATLC COAST WORKS ITS WAY BACK TOWARD THE COASTLINE TO FURTHER
REINFORCE LOCAL GRADIENTS...ESPECIALLY AT NIGHT AS OFTEN OCCURS IN
THIS FLOW REGIME.
PREVIOUS GFS RUNS SHOWED AN AREA OF LOW PRESSURE PROGGED TO DEVELOP
OVER STALLED FRONT OFFSHORE OF THE CAROLINAS AS WELL AS OVER CNTRL
GULF OF MEXICO. LATTER LOW TO MOVE TOWARD THE NRN GULF COAST ON
SATURDAY. NEWEST GUIDANCE PUSHED THIS SCENARIO TO SUNDAY AND OPENS
UP LOW TO A WAVE. THIS WOULD CREATE AN OVERRUNNING SCENARIO WITH AN
INCREASING EASTERLY FLOW IN THE LOW LEVELS AND (WITH APPROACHING
UPPER TROUGH) SOUTHWESTERLY FLOW ALOFT. THE NAM KEEP LOW WELL W OF
CWA AND IS MUCH LESS BULLISH ON THE MOISTURE RETURN. BEST CHANCE FOR
POPS WOULD BE OVER WATERS AND COASTLINES.
.SHORT TERM (TODAY THROUGH SUNDAY)...
TODAY...WITH HIGH NOSING SWWD AND FURTHER DOWN EAST COAST...WEDGE
AND COLD SURGE OF STRATUS OF RECENT DAYS ALSO TRANSLATING WWD WITH
SW ZONES BEST BET FOR ANY LOW CLOUDS EARLY...BETTER CHANCE FOR LIGHT
FOG EARLY THIS MORNING MAINLY SE ALA/SW GA. NE STEERING FLOW REGIME
AGAIN FAVORS PINNING SHALLOW SEABREEZE ALONG MAINLY PANHANDLE COAST
AND ADJACENT WATERS AFTERNOON INTO NIGHTTIME. WILL GO WITH 10-20 PCT
NE-SE POP GRADIENT. INLAND MAX TEMPS FROM MID 80S WEST TO UPPER 80S
EAST.
SATURDAY...UNDER INCREASING CLOUDS...INLAND MAX TEMPS FROM LOW 80S
NW THIRD TO MID 80S SE THIRD. ESE STEERING FLOW WITH 30 PCT POPS
MUCH OF PANHANDLE AND OVER BIG BEND COAST. AOB 20 PCT OPS
ELSEWHERE.
SUNDAY...WITH GULF LOW APPROACHING...SSE STEEPING FLOW. 40 PCT POPS
COASTAL COUNTIES AND WATERS...30 PCT ELSEWHERE. BEST CHANCES FOR
TSTMS WILL BE ACROSS WATERS AND COASTS. UNDER INCREASING CLOUDS AND
RAIN CHANCES...INLAND MAX TEMPS IN LOW 80S.
.LONG TERM....MONDAY THROUGH FRIDAY...
SURFACE WINDS WILL CONTINUE FROM THE EAST TO NORTHEAST THROUGH THE
PERIOD KEEPING LOW LEVELS FAIRLY MOIST. WEAK UPPER TROUGHING WILL
RESIDE OVER THE LOCAL AREA THROUGH TUESDAY BECOMING MORE PRONOUNCED
WEDNESDAY THROUGH FRIDAY AS A CLOSED UPPER LOW DEVELOPS OVER THE MID
ATLANTIC STATES AND LIFTS TOWARD NEW ENGLAND. AS THE TROUGH DEEPENS
...TIME HEIGHT CROSS SECTIONS SHOW A MUCH DRIER AIRMASS FILTERING IN
ABOVE 700 MB. POPS WILL BE IN THE CHANCE CATEGORY FOR MONDAY AND
TUESDAY DIMINISHING TO SLIGHT TO NIL FOR MID TO LATE WEEK.
&&
.AVIATION...BY SUNRISE WE MAY SEE AN INCREASE IN LOW CLOUDS DROPPING
CIGS TO MVFR LEVELS. THESE CLOUDS SHOULD BURN OFF FAIRLY QUICKLY BY
MID MORNING WITH VFR CONDITIONS EXPECTED THROUGH THE REMAINDER OF
THE PERIOD. A DRIER AIRMASS HAS FILTERED INTO THE MID AND UPPER
LEVELS AND THERE IS ONLY A SLIGHT CHANCE OF AN ISOLATED SHOWER OR
THUNDERSTORM THIS AFTERNOON...MAINLY NEAR THE VLD TAF SITE.
&&
.MARINE...
DURING THE PREDAWN HOURS...OFFSHORE WINDS WERE AOA 20 KTS WITH
NEARSHORE WINDS UP TO 15-20 KTS. HOISTED SCA FOR OFFSHORE AND SCEC
FOR NEARSHORE UNTIL 10 AM EDT. SEAS 3-4 FEET. WINDS WILL SUBSIDE BY
MID MORNING...HOWEVER...SURGE WILL LIKELY CONTINUE TONIGHT AND
POSSIBLY SAT NIGHT AND HEADLINES MAY BE NECESSARY.
&&
.FIRE WEATHER...EAST TO NORTHEAST FLOW WILL CONTINUE FOR NEXT
SEVERAL DAYS. INLAND BIG BEND RH MAY BRIEFLY DIP BELOW 40 PCT BUT
DURATIONS NOT EXPECTED. INCREASING MOISTURE SAT THRU SUNDAY SO NO
CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 88 65 85 66 / 05 05 20 10
PANAMA CITY 87 66 84 67 / 20 20 30 30
DOTHAN 84 62 81 62 / 10 05 20 20
ALBANY 86 62 83 63 / 0 05 20 20
VALDOSTA 87 63 83 65 / 0 05 20 20
CROSS CITY 88 66 86 67 / 10 05 20 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...SCA OFFSHORE WATERS.
&&
$$
BLOCK/BARRY
000
FXUS62 KTBW 190633
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
233 AM EDT FRI SEP 19 2008
.SHORT TERM (TODAY - SUNDAY)...A MID/UPPER LEVEL TROUGH ALONG THE FLORIDA
EAST COAST WILL SHIFT EAST A BIT TODAY WITH WEAK MID LEVEL RIDGING
BUILDING IN OVER THE PENINSULA DURING THE AFTERNOON...AS ANOTHER UPPER
TROUGH DEVELOPS OVER THE CENTRAL U.S. THROUGH SUNDAY. AT THE SURFACE
A DIFFUSED FRONTAL BOUNDARY ACROSS THE SOUTH-CENTRAL PENINSULA THIS
MORNING WILL SAG A BIT FURTHER SOUTH AS STRONG SURFACE HIGH PRESSURE
FROM NEW ENGLAND SOUTHWEST TO THE NORTHERN GULF PERSISTS THROUGH SATURDAY
AS AREAS OF LOW PRESSURE DEVELOP ALONG A STALLED FRONTAL BOUNDARY OFFSHORE
THE CAROLINAS AND OVER THE CENTRAL GULF.
A DRY SUBSIDENT AIR MASS OVERHEAD VIA MODEL SOUNDINGS/CROSS-SECTIONS
COMBINED WITH A BREEZY NORTHEASTERLY WIND FLOW LIKELY TO KEEP THE
WEST COAST SEA BREEZE AT BAY MEANS BELOW NORMAL RAIN CHANCES FOR THE
ENTIRE FORECAST AREA TODAY WITH POPS ONLY ~20% AT BEST. DURING SATURDAY
LIGHTER WINDS SHOULD ALLOW THE SEA BREEZE TO DEVELOP...BUT LIMITED
MOISTURE SHOULD AGAIN KEEP RAIN CHANCES BELOW NORMAL WITH A 20 TO 30%
POP GRADIENT FROM THE COAST TO INLAND LOCATIONS EXPECTED. ON SUNDAY
INCREASING MOISTURE SHOULD LEAD TO BETTER PROSPECTS FOR SHOWERS/STORMS
ALONG THE SEA/LAKE BREEZE BOUNDARIES DURING THE AFTERNOON...SO WILL
DEPICT POPS IN THE 30-40% RANGE. TEMPERATURES WILL BE NEAR NORMAL THROUGH
THE PERIOD. MAV/MET TEMPS ARE CLOSE SO WILL USE A BLEND.
&&
.LONG TERM (SUN NIGHT - THURSDAY)...WEAK HIGH PRESSURE WILL BE IN
PLACE ACROSS THE AREA AS A REMNANT FRONTAL BOUNDARY/WEAK SFC TROUGH
REMAINS IN PLACE OFFSHORE OF THE EASTERN FL COAST. SW FLOW IS IN
PLACE ALOFT THROUGH TUESDAY. THE TROUGH THEN SWINGS THROUGH THE
AREA LATE TUES/EARLY WED AND LEAVES W/NW FLOW OVER THE AREA
THROUGH THURS. SCATTERED RAIN CHANCES WILL BE POSSIBLE EACH AFTERNOON
AND EARLY EVENING WITH THE BEST CHANCES TUESDAY AS THE UPPER ENERGY
IS IN PLACE ACROSS THE AREA. HIGHS ARE EXPECTED MAINLY IN THE UPPER
80S WITH LOWS IN THE UPPER 60S/AROUND 70 NORTH TO THE LOWER TO MID
70S CENTRAL AND SOUTH.
&&
.AVIATION...VFR EXPECTED THROUGH THE PERIOD. A FEW LOW CLOUDS IN THE
MVFR RANGE MAY DEVELOP AROUND SUNRISE...BUT DRIER AIR IN PLACE
ACROSS THE AREA SHOULD PREVENT ANY SHOWER OR THUNDERSTORM ACTIVITY
THIS AFTERNOON.
&&
.MARINE...STRONG HIGH PRESSURE TO THE NORTH WILL SUPPORT ~4MB GRADIENT
OVER THE GULF WATERS TODAY. THIS WILL LEAD TO WINDS IN THE 15-20 KNOT
RANGE AND SEAS OF 3-5 FEET IN MY OFFSHORE WATERS FROM ENGLEWOOD
NORTH TO THE SUWANNEE RIVER...SO WILL RAISE SMALL CRAFT EXERCISE FLAGS
FOR THESE AREAS IN THE NEXT MARINE PACKAGE LATER THIS MORNING. ACROSS
THE REMAINDER OF THE GULF WATERS EXPECT NORTHEAST WINDS IN THE 10-15
KNOT RANGE WITH SEAS OF 2-4 FEET. DURING SATURDAY AND SUNDAY LIGHTER
WINDS AND LOWER SEAS ARE EXPECTED AS THE GRADIENT RELAXES WITH AN
ONSHORE SEA BREEZE COMPONENT DEVELOPING NEAR SHORE EACH AFTERNOON.
DURING EARLY NEXT WEEK WIND/SEAS MAY AGAIN BECOME ELEVATED AS THE
GRADIENT TIGHTENS AGAIN IN RESPONSE TO STRONG HIGH PRESSURE BUILDING
IN FROM NEW ENGLAND SOUTHWARD TO THE NORTHERN GULF.
&&
.FIRE WEATHER...BREEZY NORTHEAST TRANSPORT WINDS COMBINED WITH HIGH
MIXING HEIGHTS WILL LEAD TO HIGH DISPERSION INDICES ACROSS THE FORECAST
ARE TODAY. DRIER AIR MIXING DOWN TO THE SURFACE WILL YIELD LOWER HUMIDITY
(~45%) ACROSS THE REGION...BUT VALUES SHOULD REMAIN WELL ABOVE CRITICAL
LEVELS WITH NO RED FLAG CONDITIONS EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 89 72 88 73 / 20 10 20 20
FMY 91 71 91 73 / 20 10 20 20
GIF 89 70 88 72 / 20 10 30 20
SRQ 90 70 89 70 / 20 10 20 20
BKV 89 68 88 68 / 20 10 20 20
SPG 89 76 88 77 / 20 10 20 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT EXERCISE CAUTION THROUGH THIS AFTERNOON FOR
ENGLEWOOD TO SUWANNEE RIVER OUT 20 TO 60 NM AND
FROM TARPON SPRING TO SUWANNEE RIVER OUT 20 NM.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...JCM
LONG TERM/AVIATION...JLC
000
FXUS62 KMFL 190516
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
116 AM EDT FRI SEP 19 2008
.AVIATION...MOSTLY VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER
OF THE OVERNIGHT HOURS, HOWEVER A QUICK SHOWER MAY BE POSSIBLE ALONG
THE EAST COAST WITH BRIEF LOWERING OF THE CEILINGS AND VIS
POSSIBLE. BY MID TO LATE MORNING SCATTERED TSRA ARE EXPECTED TO
BEGIN DEVELOPING ACROSS S FL... VCTS HAS BEEN ADDED TO THE TAFS.
A LAND BREEZE IS EXPECTED TO LINGER INTO THE MID MORNING HOURS,
BUT ONLY TO REVERSE AS THE MORNING PROGRESSES. /TINGLER
&&
.PREV DISCUSSION... /ISSUED 927 PM EDT THU SEP 18 2008/
UPDATE...
SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT DEVELOPED EARLIER
TODAY...AS MID-LEVEL SHORTWAVE TROUGH AXIS APPROACHED SOUTH
FLORIDA...WILL CONTINUE TO AFFECT MAINLY SOUTHERN PORTIONS OF THE
FORECAST AREA OVERNIGHT. DESPITE WESTERLY COMPONENT TO FLOW
ALOFT...LATEST VWP DATA FROM KAMX WSR 88-D SUGGESTS THAT INFLUENCE
OF STRONG SURFACE RIDGING OVER THE GREAT LAKES REGION HAS ALREADY
SPREAD OVER THE REGION...WITH NORTHEAST FLOW THROUGH THE LOWEST
8-10 KFT OF THE TROPOSPHERE. THIS WILL PERSIST OVERNIGHT...AND
HAVE PLACED HIGHEST POPS OVER THE GULF WATERS AND ACROSS THE
SOUTHERN TIP OF THE PENINSULA TO ACCOUNT FOR RECENT TRENDS IN
RADAR IMAGERY. OTHERWISE...ADJUSTED WIND SPEEDS SLIGHTLY OVER THE
ATLANTIC WATERS/BISCAYNE BAY/LAKE OKEECHOBEE TO REFLECT RECENT
OBSERVATIONS. NO OTHER SIGNIFICANT CHANGES WILL BE MADE WITH THIS
UPDATE.
70/DD
AVIATION DISCUSSION... /ISSUED 817 PM EDT THU SEP 18 2008/
AVIATION...VFR CONDITIONS EXPECTED THROUGH 20/00Z. VCSH LEFT UNTIL
19/03Z FOR THE EAST COAST TERMINALS. A LIGHT NE FLOW AT ALL
TERMINALS EXPECTED TO PICK UP TO AROUND 11 KTS BY 19/15Z. LEFT
VCTS FOR THE EAST COAST ALSO BY 19/15Z. FOR KAPF...VCSH EXPECTED
BY 19/15Z WITH A NE FLOW.
/RIVERA
PREV DISCUSSION... /ISSUED 253 PM EDT THU SEP 18 2008/
DISCUSSION...MID/UPPER LEVEL TROUGH DIGGING DEEPER THAN EXPECTED
INTO NORTHEAST GULF OF MEXICO AND NORTHERN FLORIDA. THE
INFLUENCE THE THE ADVANCING DRYER AIR AND THE DEEPENING TROUGH,
HAS ME HESITANT IN LOWERING THE POPS FOR THE REST OF THIS
AFTERNOON. SOME OF THE DRIER AIR REACHES SOUTH FLORIDA BY FRIDAY
AND HANGS AROUND FOR MOST OF THE WEEKEND. THIS CHANGES THE POP
FORECAST A LITTLE. I CHANGED AFTN POPS OF 50 PERCENT FOR THE NEXT
3 AFTNS TO 40 PERCENT AND THAT MAY BE A BIT HIGH. FCSTD SOUNDINGS
INDICATE PWAT`S REACHING 1.6" BY FRIDAY AND CLIMBS A BIT SATURDAY
AND THEN TO AT LEAST 1.80 INCHES BY SUNDAY. BUT THE MID LEVELS
LOOK A BIT WARM THROUGH THE PERIOD SO IF THIS TREND CONTINUES, THE
WEEKEND MAY BE BETTER THAN EXPECTED ATTM. BY SUNDAY THE MID LEVEL
HIGH PRESSURE BUILDS BACK IN AND PUSHES THE TROUGH NORTH AND EAST.
THE LOW LEVEL TROUGH THAT WAS TALKED ABOUT PREVIOUSLY APPROACHING
SOUTH FLORIDA EARLY SUNDAY DOESN`T HAVE AS MUCH MOISTURE WITH IT
AND MUCH SHALLOWER EASTERLIES. BUT BY TUESDAY AND WEDNESDAY, MUCH
DEEPER EASTERLIES RETURN AND PWAT`S CLIMB TO AROUND 2 INCHES AND
HAVE UPPED THE POPS FOR THESE DAYS TO BE MORE IN LINE WITH THE
MEXMOS.
MARINE...WINDS WILL BE NE 5 TO 10 KNOTS TNGT THROUGH FRIDAY NIGHT
AND THEN BASICALLY E 5 TO 10 KNOTS SAT THROUGH TUES. SPEEDS WILL
BE A LITTLE HIGHER MONDAY NIGHT AND TUES SOUTHERN ATLANTIC WATERS
AND SEAS WILL BE UP TO 4 FEET IN THE GULF STREAM. LOOKED AT THE
WNAWAVE MODEL AND NOTICED A NE SIGNIFICANT WAVE HEIGHT OF 1.5
METERS FOR THIS WEEKEND. WITH THE MID LEVEL TROUGH MOVING OUT, IT
DOES PRODUCE A LOW BUT NOT AS STRONG AS PREVIOUS RUNS SO WILL HAVE
TO WAIT AND SEE IF THE WAVE WATCH MODEL CONTINUES THIS SCENARIO.
FIRE WEATHER...NO CONCERNS HERE AS THE MINIMUM RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 89 77 / 40 30 40 30
FORT LAUDERDALE 89 77 88 78 / 40 30 40 30
MIAMI 90 77 89 78 / 40 30 40 30
NAPLES 90 73 90 74 / 40 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
000
FXUS62 KMLB 190135
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
935 PM EDT THU SEP 18 2008
.DISCUSSION...
...NORTHEAST SWELLS AND INCREASING THREAT FOR RIP CURRENTS EXPECTED
AT THE BEACHES THIS WEEKEND...
CURRENTLY-TONIGHT...NORTHEAST SURGE HAS BROUGHT SOME DRIER AIR
ACROSS NORTHERN SECTIONS WITH DEW POINTS IN THE UPPER 60S. FARTHER
UPSTREAM OVER THE ATLANTIC THE DEW POINTS ARE EVEN A LITTLE LOWER.
BAND OF SCATTERED SHOWERS OVER THE ATLANTIC HAS SETTLED TO NEAR
MELBOURNE. THE ORIENTATION OF THE BAND IS BECOMING NEARLY PARALLEL
TO THE LOW LEVEL WIND FLOW...SO I AM NOT SURE THAT THE BAND WILL
MAKE A LOT FARTHER SOUTHWARD PROGRESS. HOWEVER...AN UPPER TROUGH
AXIS IS SHIFTING OFFSHORE AND WATER VAPOR LOOP IS SHOWING A LARGE
SWATH OF DRYING ALOFT ACROSS THE AREA...SO DO NOT THINK THAT THE
COVERAGE OF SHOWERS WILL BE VERY HIGH EVEN ACROSS THE SOUTH WHERE
LOW LEVEL MOISTURE WILL BE THE HIGHEST.
PLAN TO REMOVE POPS ACROSS THE INTERIOR EXCEPT MAYBE IN THE
SOUTH...AND HOLD ONTO A SLIGHT CHANCE FOR SHOWERS/STORMS SOUTH OF
CAPE CANAVERAL...AND A SLIGHT CHANCE FOR COASTAL SHOWERS NORTH OF
THE CAPE.
&&
.AVIATION...A FEW MVFR CEILINGS POSSIBLE ACROSS THE NORTH BUT
PREVAILING VFR WILL OCCUR. BRIEF IFR CONDITIONS AT KMLB-KVRB
AS ATLANTIC SHOWERS MOVE THROUGH TONIGHT. THE LATEST GFS IS QUITE
DRY FOR FRI WITH POPS 10 PERCENT OR LESS SO DO NOT EXPECT MUCH
COASTAL SHOWER ACTIVITY.
&&
.MARINE...NORTHEAST WIND SURGE IS PRODUCING DETERIORATING CONDITIONS
ACROSS THE WATERS...ESPECIALLY THE NORTH HALF. THE LATEST MARINE
MOS AT 41009 SHOWS WINDS STAYING AROUND 15 KNOTS ON FRI AND THE WAVE
WATCH IS SHOWING SEAS AT 6 FEET. THEREFORE THE CONDITIONS FOR SMALL
CRAFT WILL REMAIN POOR AND EXPECT EXERCISE CAUTION OFFSHORE IN THE
CENTRAL/NORTH. MAY HAVE TO BUMP UP TO AN EXERCISE CAUTION STATEMENT
FOR THE ADJACENT NEAR SHORE LEGS ALSO.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
LASCODY/WEITLICH
000
FXUS62 KMFL 190127
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
927 PM EDT THU SEP 18 2008
.UPDATE...
SCATTERED SHOWER/THUNDERSTORM ACTIVITY THAT DEVELOPED EARLIER
TODAY...AS MID-LEVEL SHORTWAVE TROUGH AXIS APPROACHED SOUTH
FLORIDA...WILL CONTINUE TO AFFECT MAINLY SOUTHERN PORTIONS OF THE
FORECAST AREA OVERNIGHT. DESPITE WESTERLY COMPONENT TO FLOW
ALOFT...LATEST VWP DATA FROM KAMX WSR 88-D SUGGESTS THAT INFLUENCE
OF STRONG SURFACE RIDGING OVER THE GREAT LAKES REGION HAS ALREADY
SPREAD OVER THE REGION...WITH NORTHEAST FLOW THROUGH THE LOWEST
8-10 KFT OF THE TROPOSPHERE. THIS WILL PERSIST OVERNIGHT...AND
HAVE PLACED HIGHEST POPS OVER THE GULF WATERS AND ACROSS THE
SOUTHERN TIP OF THE PENINSULA TO ACCOUNT FOR RECENT TRENDS IN
RADAR IMAGERY. OTHERWISE...ADJUSTED WIND SPEEDS SLIGHTLY OVER THE
ATLANTIC WATERS/BISCAYNE BAY/LAKE OKEECHOBEE TO REFLECT RECENT
OBSERVATIONS. NO OTHER SIGNIFICANT CHANGES WILL BE MADE WITH THIS
UPDATE.
70/DD
&&
.AVIATION DISCUSSION... /ISSUED 817 PM EDT THU SEP 18 2008/
AVIATION...VFR CONDITIONS EXPECTED THROUGH 20/00Z. VCSH LEFT UNTIL
19/03Z FOR THE EAST COAST TERMINALS. A LIGHT NE FLOW AT ALL
TERMINALS EXPECTED TO PICK UP TO AROUND 11 KTS BY 19/15Z. LEFT
VCTS FOR THE EAST COAST ALSO BY 19/15Z. FOR KAPF...VCSH EXPECTED
BY 19/15Z WITH A NE FLOW.
/RIVERA
.PREV DISCUSSION... /ISSUED 253 PM EDT THU SEP 18 2008/
DISCUSSION...MID/UPPER LEVEL TROUGH DIGGING DEEPER THAN EXPECTED
INTO NORTHEAST GULF OF MEXICO AND NORTHERN FLORIDA. THE
INFLUENCE THE THE ADVANCING DRYER AIR AND THE DEEPENING TROUGH,
HAS ME HESITANT IN LOWERING THE POPS FOR THE REST OF THIS
AFTERNOON. SOME OF THE DRIER AIR REACHES SOUTH FLORIDA BY FRIDAY
AND HANGS AROUND FOR MOST OF THE WEEKEND. THIS CHANGES THE POP
FORECAST A LITTLE. I CHANGED AFTN POPS OF 50 PERCENT FOR THE NEXT
3 AFTNS TO 40 PERCENT AND THAT MAY BE A BIT HIGH. FCSTD SOUNDINGS
INDICATE PWAT`S REACHING 1.6" BY FRIDAY AND CLIMBS A BIT SATURDAY
AND THEN TO AT LEAST 1.80 INCHES BY SUNDAY. BUT THE MID LEVELS
LOOK A BIT WARM THROUGH THE PERIOD SO IF THIS TREND CONTINUES, THE
WEEKEND MAY BE BETTER THAN EXPECTED ATTM. BY SUNDAY THE MID LEVEL
HIGH PRESSURE BUILDS BACK IN AND PUSHES THE TROUGH NORTH AND EAST.
THE LOW LEVEL TROUGH THAT WAS TALKED ABOUT PREVIOUSLY APPROACHING
SOUTH FLORIDA EARLY SUNDAY DOESN`T HAVE AS MUCH MOISTURE WITH IT
AND MUCH SHALLOWER EASTERLIES. BUT BY TUESDAY AND WEDNESDAY, MUCH
DEEPER EASTERLIES RETURN AND PWAT`S CLIMB TO AROUND 2 INCHES AND
HAVE UPPED THE POPS FOR THESE DAYS TO BE MORE IN LINE WITH THE
MEXMOS.
MARINE...WINDS WILL BE NE 5 TO 10 KNOTS TNGT THROUGH FRIDAY NIGHT
AND THEN BASICALLY E 5 TO 10 KNOTS SAT THROUGH TUES. SPEEDS WILL
BE A LITTLE HIGHER MONDAY NIGHT AND TUES SOUTHERN ATLANTIC WATERS
AND SEAS WILL BE UP TO 4 FEET IN THE GULF STREAM. LOOKED AT THE
WNAWAVE MODEL AND NOTICED A NE SIGNIFICANT WAVE HEIGHT OF 1.5
METERS FOR THIS WEEKEND. WITH THE MID LEVEL TROUGH MOVING OUT, IT
DOES PRODUCE A LOW BUT NOT AS STRONG AS PREVIOUS RUNS SO WILL HAVE
TO WAIT AND SEE IF THE WAVE WATCH MODEL CONTINUES THIS SCENARIO.
FIRE WEATHER...NO CONCERNS HERE AS THE MINIMUM RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 88 75 89 / 30 40 30 40
FORT LAUDERDALE 78 89 77 88 / 40 40 30 40
MIAMI 78 90 77 89 / 50 40 30 40
NAPLES 73 90 73 90 / 50 40 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...70/DD
SHORT TERM/AVIATION...47/RHG
000
FXUS62 KKEY 190113
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
915 PM EDT THU SEP 18 2008
.DISCUSSION...
.CURRENTLY...
KBYX DETECTS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THROUGHOUT
THE FORECAST AREA. SKIES OVER THE ISLAND CHAIN ARE PARTLY CLOUDY.
WINDS OVER LAND ARE NORTHEAST TO EAST AT 10 TO 15 MPH. C-MAN
WINDS...ON AVERAGE...ARE NORTHEAST TO EAST NEAR 15 KNOTS...WITH
GUSTS NEAR 20 KNOTS. TEMPERATURES ARE IN THE LOWER 80S. ONLY ABOUT
FOUR DEGREES OF COOLING IS EXPECTED OVERNIGHT DUE TO GENTLE
NORTHEAST TO EAST SURFACE WINDS OVER WATER WITH TEMPERATURES IN THE
MID 80S.
.SHORT TERM (OVERNIGHT)...
IN THE LOW TO MID LEVELS OF THE ATMOSPHERE...A TROPICAL WAVE IS
LOCATED ALONG 72W SOUTH OF 19N. THIS TROPICAL WAVE WILL MOVE TO THE
WEST AT 10 TO 15 KNOTS OVERNIGHT. BY SUNRISE FRIDAY...THE NORTHERN
EXTENT OF THIS TROPICAL WAVE SHOULD BE APPROACHING THE SOUTHEASTERN
COAST OF CUBA. IN THE UPPER LEVELS OF THE ATMOSPHERE...A TROUGH OF
LOW PRESSURE OVER THE FLORIDA PENINSULA SHOULD MOVE EASTWARD OVER
THE BAHAMAS TONIGHT. THE 00Z KKEY SOUNDING IS MODERATELY UNSTABLE
AND TYPICALLY MOIST FOR MID SEPTEMBER...WITH A PRECIPITABLE WATER
(PWAT) VALUE JUST ABOVE ONE AND THREE QUARTERS OF AN INCH.
ATMOSPHERIC MOISTURE MAY DECREASE OVERNIGHT. BY SUNRISE FRIDAY...
PWAT VALUES MAY BE JUST BELOW ONE AND THREE QUARTERS OF AN INCH.
THERE IS ENOUGH MOISTURE AND INSTABILITY IN PLACE TO SUPPORT
CONVECTION TONIGHT. THE UPPER LEVEL TROUGH OF LOW PRESSURE OVER THE
FLORIDA PENINSULA MAY PROVIDE LIMITED SYNOPTIC SCALE ASCENT
TONIGHT...BEFORE PASSING EAST OF THE FLORIDA PENINSULA. AS A
RESULT...THERE IS RELUCTANCE TO ADVERTISE POPS BELOW MIDDLE OF THE
ROAD CHANCE CATEGORY FOR TONIGHT...UNTIL THE AFOREMENTIONED UPPER
LEVEL TROUGH OF LOW PRESSURE PASSES EAST OF THE FLORIDA PENINSULA.
THE CURRENT ZONE FORECASTS FOR THE FLORIDA KEYS HANDLES THIS
SITUATION WELL...SO NO ADDITIONAL UPDATES ARE EXPECTED.
&&
.MARINE...
MODERATE NORTHEAST TO EAST SURFACE WINDS WILL PREVAIL ON ALL KEYS
WATERS OVERNIGHT. NO ADVISORIES OR CAUTIONARY STATEMENTS EXPECTED
TONIGHT THROUGH AT LEAST TUESDAY.
&&
.AVIATION...
A BRIEF ROUND OR TWO OF MVFR/IFR CONDITIONS ARE POSSIBLE AT THE
ISLAND TERMINALS OVERNIGHT...AS SCATTERED SHOWERS WITH A FEW
EMBEDDED THUNDERSTORMS TRACK SOUTHWESTWARD AT AROUND 15 KNOTS
THROUGH THE WATERS SURROUNDING THE FLORIDA KEYS. SURFACE WINDS WILL
BE OUT OF THE EAST NORTHEAST AT 5 TO 10 KNOTS.
&&
.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...IN 1926...THE GREAT MIAMI
HURRICANE OF 1926 MADE LANDFALL JUST SOUTH OF MIAMI AS A CATEGORY 4
HURRICANE. HURRICANE FORCE WINDS IN THE UPPER KEYS SEVERELY DAMAGED
THE ROADWAY AND BRIDGES BEING BUILT. IN KEY WEST...THE MINIMUM
PRESSURE WAS 29.48 INCHES AND THE PEAK WIND WAS 52 MPH. THE GREAT
MIAMI HURRICANE OF 1926 IS THE 13TH MOST INTENSE HURRICANE TO EVER
STRIKE THE UNITED STATES.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE/FIRE/CLIMATE/DIGITAL...BS
AVIATION/NOWCASTS....................11
DATA ACQUISITION.....................DR
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KJAX 190102
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
902 PM EDT THU SEP 18 2008
.UPDATE...UPPER SHORTWAVE TROUGH JUST EAST OF THE AREA AND
PULLING AWAY WITH VERY DRY AIR IN MID AND UPPER LEVELS AS SHOWN BY
WATER VAPOR AND 00Z SOUNDING. EARLIER SHOWER ACTIVITY HAS
DISSIPATED AND WILL DELETE POPS FROM TONIGHTS FORECAST DESPITE
STRONG NE CONVERGENT FLOW ALONG THE COASTLINE. DRY AIR AT SURFACE
ALSO ADVECTING INTO AREA SO DON`T EXPECT SHOWER ACTIVITY
OVERNIGHT. NO OTHER CHANGES EXPECTED TO PREVIOUS FORECAST.
&&
.AVIATION...
MOSTLY CLEAR SKIES PROVIDING VFR CONDITIONS AT ALL TERMINALS THIS
EVENING. COOLER DEWPOINTS AND TIGHTER GRADIENT NOT LIKELY TO ALLOW
A REPEAT OF DENSE FOG TONIGHT...AT LEAST ALONG THE IMMEDIATE
COAST. DEWPOINTS NOT QUITE AS LOW AT GNV WHERE THE BOUNDARY LAYER
HAS THE BEST CHANCE OF DECOUPLING...THUS RESULTING IN BETTER
CONDITIONS FOR FOG DEVELOPMENT OVERNIGHT. ALSO CANNOT RULE OUT THE
POSSIBILITY OF LOW CLOUDS DEVELOPING AFTER MIDNIGHT GIVEN
RELATIVELY MOIST BOUNDARY LAYER IN NORTHEAST FLOW. SCATTERED TO
BROKEN LOW CLOUDS WILL FLIRT WITH MVFR AT TIMES ON FRIDAY. VCSH
WILL ACCOUNT FOR ISOLATED COASTAL SHOWERS THROUGH THE DAY.
&&
.MARINE...
SOLID SCEC CONDITIONS ARE BEING OBSERVED THIS EVENING ACROSS ALL
MARINE ZONES...NORTHEAST WINDS 15 TO 20 KNOTS AND SEAS 5 TO 6
FEET. SCA CONDITIONS WILL TAKE OVER BY MORNING WITH SUSTAINED
NORTHEAST WINDS OF AT LEAST 20 KNOTS AND SEAS CLIMBING TO 7 TO 8
FEET.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 84 62 85 62 / 20 20 10 10
SSI 82 70 81 69 / 40 10 20 20
JAX 84 69 83 68 / 40 20 20 20
SGJ 83 72 83 72 / 40 30 30 30
GNV 86 66 86 66 / 40 30 10 10
OCF 89 67 87 67 / 40 40 10 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 7 AM FRIDAY TO 10 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 11 AM FRIDAY TO 4 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.
&&
$$
ZIBURA/SHULER/KEEGAN
000
FXUS62 KTBW 190049
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
849 PM EDT THU SEP 18 2008
.UPDATE...WV SAT IMAGERY SHOWING DRY AIR ALOFT WRAPPING AROUND
BASE OF TROF DOWN THE EASTERN SEABOARD AND OVER MUCH OF THE FL
PENINSULA. SFC FRONT STALLED OVER THE S CENTRAL FL PENINSULA WITH
DRY DEWPOINTS DOWN INTO THE UPPER 60S AS FAR SOUTH AS SRQ. AFTERNOON
AND EVENING CONVECTION PERSISTS IN SW FL JUST AHEAD AND ALONG
FRONT BECOMING ISOLATED AND MOVING OFFSHORE ATTM. 00Z SOUNDING
SHOWING DRY AIR ALOFT WITH INVERSION ABOVE 12K FT AND DRY INVERTED
V NEAR THE SFC. OVERNIGHT EXPECT DRYING CONDITIONS WITH TEMPS
FALLING A FEW DEGREES BELOW NORMAL AS LATEST FORECAST AND GRIDS SHOWING.
&&
.MARINE...STALLED FRONT OVER THE E GULF KEEPING LIGHT WINDS AND
SEAS OVER THE AREA OUTSIDE CONVECTION. LATEST BUOY REPORTS HAVE
WINDS AROUND 10 KT AND SEAS AROUND 2 FT. LATEST FORECAST ON TRACK.
&&
.AVIATION...HAVE SOME SHOWERS AND STORMS OVER SOUTHWEST FLORIDA THAT
WILL CONTINUE FOR THE NEXT HOUR OR SO. THEN WILL HAVE TO WATCH FOR
LOW CLOUDS TO DEVELOP OVERNIGHT. HAVE KEPT PREVIOUS FORECAST FOR A
FEW CLOUDS AROUND 1500 FEET...BUT CHANGED THE TIMING CLOSER TO
DAYLIGHT. THEN FOR TOMORROW AFTERNOON...MODELS ARE COMING IN LOWER
FOR STORM CHANCES. FOR NOW HAVE LEFT OUT VICINITY WORDING AND JUST
HAVE SCATTERED CIRRUS.
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
RD/RJS
000
FXUS62 KTAE 190045
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
845 PM EDT THU SEP 18 2008
.DISCUSSION...00 UTC SURFACE ANALYSIS CONTINUES TO SHOW RIDGING
NOSING DOWN THE LEE SIDE OF THE APPALACHIANS INTO NORTH FLORIDA. THE
RESULTANT PRESSURE GRADIENT APPEARS TIGHTER THAN JUST A FEW HOURS
AGO. A STATIONARY FRONT REMAINS LOCATED ACROSS SOUTH CENTRAL
FLORIDA. THE REAL HUMID AIR IS LOCATED SOUTH OF THIS
BOUNDARY...THOUGH IN OUR AREA DEWPOINTS ARE NEAR THE 70 DEGREE MARK
IN THE PANHANDLE.
UPPER AIR DATA FROM KTAE SHOWS A STRONG SUBSIDENCE INVERSION ABOVE
650 MB. THE AIRMASS IS QUITE DRY ABOVE THIS LEVEL. THIS WOULD SEEM
TO CONFIRM EXACTLY WHAT THE VAPOR IMAGERY IS SHOWING ACROSS THE
SOUTHEAST...WITH A LARGE POCKET OF MID AND UPPER LEVEL DRY AIR THAT
STRETCHES FROM TENNESSEE TO THE CAROLINAS AND DOWN INTO FLORIDA.
STRONG NORTHEASTERLY FLOW AT THE SURFACE AND UP TO 700 MB MAXIMIZED
CONVERGENCE ALONG A WEAK SEA BREEZE FRONT ALONG THE PANHANDLE AND
LED TO SCATTERED SHOWERS AND THUNDERSTORMS BETWEEN WALTON AND GULF
COUNTIES. RADAR CONTINUES TO INDICATE A PERSISTENT STORM OVER
CENTRAL AND WESTERN BAY COUNTY. CONVENTIONAL WISDOM WOULD SUGGEST
THAT THIS STORM WOULD DIMINISH OVER THE NEXT COUPLE OF HOURS AS THE
SEA BREEZE CIRCULATION HAS STOPPED. NEVERTHELESS...THE 18/18Z NAM
INITIALIZED THIS CONVECTION WELL AND HAS IT CONTINUING AND SPREADING
WESTWARD THROUGH 06Z. WILL MONITOR THE RADAR FOR THE NEXT HOUR OR
SO...BUT MAY NEED TO UPDATE THE FORECAST TO INCLUDE RAIN CHANCES FOR
THE WESTERN PANHANDLE OVERNIGHT. THE REMAINDER OF THE FORECAST IS IN
GOOD SHAPE WITH NO OTHER SIGNIFICANT CHANGES NEEDED. HAVE A GREAT
NIGHT!
&&
.AVIATION...
CONVECTION WAS ISOLATED TODAY WITH THE EXCEPTION OF AROUND PFN WHERE
A BIT MORE CONCENTRATION WAS NOTED. EXPECT THIS TO DIE OFF BY
AROUND 03Z AND HAVE ACCOUNTED FOR THIS WITH A TEMPO GROUP FOR PFN.
OTHERWISE, EXPECT SOME DRIER LOW LEVEL AIR TO BEGIN TO FILTER IN
OVERNIGHT SO WILL HAVE MOSTLY VFR CONDITIONS OVERNIGHT. HOWEVER, BY
EARLY MORNING WE MAY SEE AN INCREASE IN LOW CLOUDS ONCE AGAIN
DROPPING CIGS TO MVFR LEVELS. THESE CLOUDS SHOULD BURN OFF FAIRLY
QUICKLY BY MID MORNING THOUGH WITH VFR CONDITIONS EXPECTED THROUGH
THE REMAINDER OF FRIDAY.
&&
.MARINE...
WINDS AND SEAS ARE IN THE 10 KT AND 2 TO 3 FOOT RANGE RESPECTIVELY
THIS EVENING. WITH THE GRADUALLY TIGHTENING GRADIENT TO THE
NORTH...WOULD NOT BE SURPRISED TO SEE THE FAVORED NOCTURNAL SURGE IN
NORTHEASTERLY FLOW REGIMES. THINK THE WINDS WILL STAY BELOW EXERCISE
CAUTION CRITERIA...BUT NEVERTHELESS...WINDS PEAKING AROUND 17KT
OVERNIGHT WITH SEAS POTENTIALLY BUILDING TO NEAR 5 FEET WELL
OFFSHORE WILL BE POSSIBLE. THIS WILL LIKELY CONTINUE EACH NIGHT OVER
THE NEXT COUPLE OF DAYS. WINDS AND SEAS WILL GRADUALLY DIMINISH
THOUGH BY MID MORNING EACH DAY.
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
AVIATION...VAN DYKE/WOOL
REST OF DISCUSSION...GODSEY
000
FXUS62 KMFL 190017
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
817 PM EDT THU SEP 18 2008
.AVIATION...VFR CONDITIONS EXPECTED THROUGH 20/00Z. VCSH LEFT
UNTIL 19/03Z FOR THE EAST COAST TERMINALS. A LIGHT NE FLOW AT ALL
TERMINALS EXPECTED TO PICK UP TO AROUND 11 KTS BY 19/15Z. LEFT VCTS
FOR THE EAST COAST ALSO BY 19/15Z. FOR KAPF...VCSH EXPECTED BY
19/15Z WITH A NE FLOW.
/RIVERA
&&
.PREV DISCUSSION... /ISSUED 253 PM EDT THU SEP 18 2008/
DISCUSSION...MID/UPPER LEVEL TROUGH DIGGING DEEPER THAN EXPECTED
INTO NORTHEAST GULF OF MEXICO AND NORTHERN FLORIDA. THE INFLUENCE
THE THE ADVANCING DRYER AIR AND THE DEEPENING TROUGH, HAS ME
HESITANT IN LOWERING THE POPS FOR THE REST OF THIS AFTERNOON. SOME
OF THE DRIER AIR REACHES SOUTH FLORIDA BY FRIDAY AND HANGS AROUND
FOR MOST OF THE WEEKEND. THIS CHANGES THE POP FORECAST A LITTLE. I
CHANGED AFTN POPS OF 50 PERCENT FOR THE NEXT 3 AFTNS TO 40 PERCENT
AND THAT MAY BE A BIT HIGH. FCSTD SOUNDINGS INDICATE PWAT`S
REACHING 1.6" BY FRIDAY AND CLIMBS A BIT SATURDAY AND THEN TO AT
LEAST 1.80 INCHES BY SUNDAY. BUT THE MID LEVELS LOOK A BIT WARM
THROUGH THE PERIOD SO IF THIS TREND CONTINUES, THE WEEKEND MAY BE
BETTER THAN EXPECTED ATTM. BY SUNDAY THE MID LEVEL HIGH PRESSURE
BUILDS BACK IN AND PUSHES THE TROUGH NORTH AND EAST. THE LOW LEVEL
TROUGH THAT WAS TALKED ABOUT PREVIOUSLY APPROACHING SOUTH FLORIDA
EARLY SUNDAY DOESN`T HAVE AS MUCH MOISTURE WITH IT AND MUCH
SHALLOWER EASTERLIES. BUT BY TUESDAY AND WEDNESDAY, MUCH DEEPER
EASTERLIES RETURN AND PWAT`S CLIMB TO AROUND 2 INCHES AND HAVE
UPPED THE POPS FOR THESE DAYS TO BE MORE IN LINE WITH THE MEXMOS.
MARINE...WINDS WILL BE NE 5 TO 10 KNOTS TNGT THROUGH FRIDAY NIGHT
AND THEN BASICALLY E 5 TO 10 KNOTS SAT THROUGH TUES. SPEEDS WILL
BE A LITTLE HIGHER MONDAY NIGHT AND TUES SOUTHERN ATLANTIC WATERS
AND SEAS WILL BE UP TO 4 FEET IN THE GULFSTREAM. LOOKED AT THE
WNAWAVE MODEL AND NOTICED A NE SIGNIFICANT WAVE HEIGHT OF 1.5
METERS FOR THIS WEEKEND. WITH THE MID LEVEL TROUGH MOVING OUT, IT
DOES PRODUCE A LOW BUT NOT AS STRONG AS PREVIOUS RUNS SO WILL HAVE
TO WAIT AND SEE IF THE WAVE WATCH MODEL CONTINUES THIS SCENARIO.
FIRE WEATHER...NO CONCERNS HERE AS THE MINIMUM RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 88 75 89 / 40 40 30 40
FORT LAUDERDALE 78 89 77 88 / 40 40 30 40
MIAMI 78 90 77 89 / 40 40 30 40
NAPLES 73 90 73 90 / 30 40 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...70/DD
SHORT TERM/AVIATION...47/RHG
000
FXUS62 KKEY 181955
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
355 PM EDT THU SEP 18 2008
.DISCUSSION...
A WEAK AND BROAD CYCLONIC FLOW IN THE UPPER TROPOSPHERE COVERS MUCH
OF THE EASTERN GULF BASIN AND FLORIDA PENINSULA...WITH A MIGRATORY
SHORT-WAVE TROUGH CURRENTLY MOVING ACROSS THE SOUTHEASTERN UNITED
STATES. THE TROUGH AXIS MAY EXTEND FAR ENOUGH SOUTH TO SUPPORT WEAK
ASCENT ON THE SYNOPTIC-SCALE OVER SOUTHERN FLORIDA.
CURRENT RADAR OBSERVATIONS SHOW A PLETHORA OF BOUNDARIES OVER THE
SERVICE AREA...INDUCED BY BOTH TERRAIN AND CONVECTION. A LARGE
CLUSTER OF SHOWERS AND THUNDERSTORMS IS MOVING SOUTHWESTWARD ACROSS
THE WATERS BETWEEN CAPE SABLE AND THE LOWER KEYS...AND IT APPEARS AS
IF MANY LOWER KEYS COMMUNITIES ARE ABOUT TO RECEIVE MEASURABLE
RAINFALL IN THE NEXT ONE TO TWO HOURS.
THE LARGE SCALE WEATHER PATTERN IS EXPECTED TO CHANGE ONLY VERY
SLOWLY OVER THE NEXT THREE TO FIVE DAYS...SO FRIDAY AND SATURDAY WILL
FEATURE A WEATHER REGIME SIMILAR TO THAT OF TODAY AND YESTERDAY.
MOISTURE WILL REMAIN ABUNDANT IN THE LOWER TROPOSPHERE AND THE
ATMOSPHERE WILL REMAIN MODERATELY UNSTABLE WITH WEAK INHIBITION. IN
ADDITION...THERE IS A NOTABLE LACK OF DEEP RIDGING AND ASSOCIATED
WEAK SUBSIDENCE...SO LOCAL MESOSCALE CIRCULATIONS WILL BE VERY
EFFECTIVE IN PRODUCING SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
WINDS AND SEAS WILL BE HIGHER AND ROUGH IN AND NEAR SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND THIS
EVENING...WITH DECREASING SHOWER AND STORM COVERAGE OVERNIGHT. A
NEAR REPEAT SEEMS INCREASINGLY LIKELY FOR FRIDAY/FRIDAY NIGHT.
OUTSIDE OF SHOWERS/STORMS...NORTHEAST TO EAST WINDS WILL FRESHEN AS
HIGH PRESSURE BUILDS NORTH OF THE KEYS...WITH MODERATE EAST BREEZES
IN STORE BY EARLY NEXT WEEK.
&&
.AVIATION...
A SPELL OF MVFR CONDITIONS IS LIKELY AT THE EYW AND MTH TERMINALS
FOR THE REMAINDER OF THIS AFTERNOON AND EVENING. OUTSIDE OF SHOWERS
AND THUNDERSTORMS...MOSTLY NORTHEAST WINDS OF 10 KNOTS OR LESS CAN
BE ANTICIPATED...BEFORE BECOMING LIGHT AND VARIABLE OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
KEY WEST 79 88 79 88 / 50 40 40 30
MARATHON 79 89 79 89 / 50 40 40 30
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........KASPER
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......ROSS
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KJAX 181854
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
252 PM EDT THU SEP 18 2008
...WATERSPOUTS REMAIN POSSIBLE THROUGH THIS EVENING...
.SHORT TERM...INITIAL FRONTAL BOUNDARY...AS INDICATED BY MSAS
ANALYSIS...HAS MADE ITS WAY INTO CENTRAL FLORIDA WITH A MILDER AND
SLIGHTLY DRIER AIRMASS IN ITS WAKE. DEWPOINT PACKING OVER THE
NORTHERN COASTLINE OF THE GEORGIA PORTION INDICATES A SECONDARY
BOUNDARY IN THE VICINITY. THIS FEATURE ALONG WITH INCREASED SPEED
CONVERGENCE IN SURFACE NORTHEAST FLOW REGIME LIKELY AIDED IN THE
OFFSHORE CONVECTIVE CLUSTER EXPERIENCED MOST OF THE MORNING HOURS.
ALTHOUGH ACTIVITY WAS GENERALLY BENIGN IN NATURE...A FEW SPINUPS
RESULTED IN NUMEROUS FUNNEL CLOUD SIGHTINGS OFFSHORE JAX BEACH AND
PONTE VEDRA.
AS IS TYPICAL IN THESE SETUPS...CONVERGENCE ALONG THE COAST HAS
EASED AND OUTFLOWS GENERATED BY EARLIER ACTIVITY CONTINUES TO
PROPAGATE SOUTH AND WESTWARD INITIATING ADDITIONAL SHOWER
DEVELOPMENT. AS MENTIONED IN PREVIOUS DISCUSSION...WE WILL STILL
BE DEALING WITH RESIDUAL SHORTWAVE ENERGY WHICH MAY PRODUCE INLAND
THUNDERSTORM ACTIVITY...BUT OVERALL STRENGTH OF STORMS WILL BE
SEVERELY LIMITED BY AMOUNT OF DRY AIR ALOFT.
FOR THE TONIGHT PERIOD...WILL KEEP PATCHY FOG WORDING IN BUT
CANNOT SEE ANYTHING BEYOND THAT GIVEN INCREASED FLOW ENVIRONMENT
WHICH SHOULD KEEP ATMOSPHERE WELL MIXED.
FRIDAY LOOKS TO BE A TRANSITION DAY...BUT A GENERALLY QUIESCENT
TRANSITION IT WILL BE. FRONTAL BOUNDARY WILL CONTINUE TO SINK
SOUTHWARD WITH DRY AIR FILTERING IN ITS WAKE...ESPECIALLY AT THE
UPPER LEVELS. STILL WILL NOT BE ABLE TO RID OURSELVES OF THE
SURFACE MOISTURE HOWEVER...AND WITH NORTHEAST FLOW
CONTINUING...COASTAL SHOWERS WILL REMAIN POSSIBLE. STILL SOME
UNCERTAINTY AS TO HOW MUCH SURFACE CONVERGENCE WILL EXIST AS GFS
SHOWS A LOW DEVELOPMENT WELL OFFSHORE WHILE THE ECMWF SHOWS MORE
OF AN OPEN WAVE. WILL FAVOR THE ECMWF FOR NOW AND INDICATE LOW END
CHANCE POPS FOR THE IMMEDIATE COASTLINE.
WE LOOK TO BE IN BETWEEN MAJOR SYSTEMS FOR THE WEEKEND AS INVERTED
TROUGH OFF THE COAST WORKS ITS WAY BACK TOWARD THE AREA AND A
STRONG SHORTWAVE DIVES INTO THE GULF INITIATING CYCLOGENESIS ALONG
THE NORTHERN GULF COAST. FEEL MOST OF OUR SENSIBLE WEATHER WILL
INITIALLY COME FROM THE COASTAL CONVERGENCE SIDE WITH SHOWERS
POOLING ALONG THE COAST AND GRADUALLY SPREADING INLAND DURING THE
DAYTIME HOURS. ALTHOUGH SHORTWAVE ENERGY MAY ENHANCE ATLANTIC SHOWER
AND THUNDERSTORM ACTIVITY...PANHANDLE STORMS SHOULD REMAIN WEST OF
THE AREA THROUGH THE SHORT TERM.
.LONG TERM...SHORTWAVE MOVES THROUGH EARLY NEXT WEEK WITH
ADDITIONAL CYCLOGENESIS POSSIBLE OVER THE OFFSHORE WATERS MONDAY
NIGHT. LONG TERM MODELS IN REMARKABLE AGREEMENT ON THIS BEING SO
FAR OUT. SUCH A SCENARIO WOULD ALLOW FOR A LOCAL NORTHEAST FLOW
EVENT TO DEVELOP WITH CLOUDY...WINDY AND WET CONDITIONS POSSIBLE
THROUGH THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...SCT-BKN CU NEAR THE HIGH END OF MVFR CIG OVER THE AREA
WILL BEGIN TO DISSIPATE THIS EVENING WITH PREVAILING VFR EXPECTED
TONIGHT. SOME LIGHT FOG WILL BE POSSIBLE TOWARD SUNRISE ESPECIALLY
AROUND GNV WHERE BOUNDARY LAYER HAS BETTER CHANCE OF DECOUPLING.
MAINLY SCT CU FOR FRIDAY WITH MAINLY ISOLD SHOWER/STORM ACTIVITY.
&&
.MARINE...SCEC CONDS EXPECTED THROUGH TONIGHT WITH TIGHTENING PRES
GRADIENT SUPPORTING WINDS UP TO 20 KT ON FRIDAY WITH SEAS BUILDING
SEAS TO 6 TO 8 FEET. THIS GRADIENT MAY RELAX A BIT ON SUNDAY AS
INVERTED TROUGH DEVELOPS ALONG THE COASTAL AREAS BUT SEAS WILL STILL
BE HAZARDOUS TO SMALL BOATERS DUE TO THE FAIRLY LONG FETCH OF NE
WINDS. APPEARS NELY FLOW WILL CONTINUE FOR MUCH OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 62 85 62 82 / 20 10 10 30
SSI 70 81 69 80 / 10 20 20 40
JAX 69 83 68 82 / 20 20 20 40
SGJ 72 83 72 82 / 30 30 30 50
GNV 66 86 66 85 / 30 10 10 40
OCF 67 87 67 86 / 40 10 10 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 7 AM FRIDAY TO 4 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 11 AM FRIDAY TO 1 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.
&&
$$
DEESE/SHASHY/KEEGAN
000
FXUS62 KMFL 181853
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
253 PM EDT THU SEP 18 2008
.DISCUSSION...MID/UPPER LEVEL TROUGH DIGGING DEEPER THAN EXPECTED
INTO NORTHEAST GULF OF MEXICO AND NORTHERN FLORIDA. THE INFLUENCE
THE THE ADVANCING DRYER AIR AND THE DEEPENING TROUGH, HAS ME
HESITANT IN LOWERING THE POPS FOR THE REST OF THIS AFTERNOON. SOME
OF THE DRIER AIR REACHES SOUTH FLORIDA BY FRIDAY AND HANGS AROUND
FOR MOST OF THE WEEKEND. THIS CHANGES THE POP FORECAST A LITTLE. I
CHANGED AFTN POPS OF 50 PERCENT FOR THE NEXT 3 AFTNS TO 40 PERCENT
AND THAT MAY BE A BIT HIGH. FCSTD SOUNDINGS INDICATE PWAT`S
REACHING 1.6" BY FRIDAY AND CLIMBS A BIT SATURDAY AND THEN TO AT
LEAST 1.80 INCHES BY SUNDAY. BUT THE MID LEVELS LOOK A BIT WARM
THROUGH THE PERIOD SO IF THIS TREND CONTINUES, THE WEEKEND MAY BE
BETTER THAN EXPECTED ATTM. BY SUNDAY THE MID LEVEL HIGH PRESSURE
BUILDS BACK IN AND PUSHES THE TROUGH NORTH AND EAST. THE LOW LEVEL
TROUGH THAT WAS TALKED ABOUT PREVIOUSLY APPROACHING SOUTH FLORIDA
EARLY SUNDAY DOESN`T HAVE AS MUCH MOISTURE WITH IT AND MUCH
SHALLOWER EASTERLIES. BUT BY TUESDAY AND WEDNESDAY, MUCH DEEPER
EASTERLIES RETURN AND PWAT`S CLIMB TO AROUND 2 INCHES AND HAVE
UPPED THE POPS FOR THESE DAYS TO BE MORE IN LINE WITH THE MEXMOS.
&&
.MARINE...WINDS WILL BE NE 5 TO 10 KNOTS TNGT THROUGH FRIDAY NIGHT
AND THEN BASICALLY E 5 TO 10 KNOTS SAT THROUGH TUES. SPEEDS WILL
BE A LITTLE HIGHER MONDAY NIGHT AND TUES SOUTHERN ATLANTIC WATERS
AND SEAS WILL BE UP TO 4 FEET IN THE GULFSTREAM. LOOKED AT THE
WNAWAVE MODEL AND NOTICED A NE SIGNIFICANT WAVE HEIGHT OF 1.5
METERS FOR THIS WEEKEND. WITH THE MID LEVEL TROUGH MOVING OUT, IT
DOES PRODUCE A LOW BUT NOT AS STRONG AS PREVIOUS RUNS SO WILL HAVE
TO WAIT AND SEE IF THE WAVE WATCH MODEL CONTINUES THIS SCENARIO.
&&
.FIRE WEATHER...NO CONCERNS HERE AS THE MINIMUM RH`S WILL BE ABOVE
CRITICAL VALUES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 88 75 89 / 40 40 30 40
FORT LAUDERDALE 78 89 77 88 / 40 40 30 40
MIAMI 78 90 77 89 / 40 40 30 40
NAPLES 73 90 73 90 / 30 40 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...18/GR
SHORT TERM/AVIATION...30/KOB
000
FXUS62 KTAE 181834 CCA
AFDTAE
AREA FORECAST DISCUSSION...CORRECTED PRELIMINARY POINT TEMPS/POPS
NATIONAL WEATHER SERVICE TALLAHASSEE FL
200 PM EDT THU SEP 18 2008
.SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...THE EAST COAST
MID/UPPER TROUGH WILL MOVE OFFSHORE WITH SHORT WAVE RIDGING IN ITS
WAKE TONIGHT. ALL OF THE NUMERICAL MODELS DEVELOP A TROUGH ACROSS
THE CENTRAL U.S. ON FRIDAY. THIS TROUGH WILL REMAIN ANCHORED TO OUR
WEST THROUGH THE WEEKEND. A STRONG SURFACE RIDGE CENTERED OVER THE
GREAT LAKES TONIGHT WILL TRANSLATE EASTWARD THROUGH NORTHERN NEW
ENGLAND AND SOUTHEASTERN CANADA. MEANWHILE...AN AREA OF LOW PRESSURE
IS PROGGED TO TAKE SHAPE ALONG A STALLED FRONT OVER THE WESTERN GULF
OF MEXICO AND MOVE TOWARD THE NRN GULF COAST ON SATURDAY. THIS WILL
CREATE AN OVERRUNNING SCENARIO WITH AN INCREASING EASTERLY FLOW IN
THE LOW LEVELS AND SOUTHWESTERLY FLOW ALOFT. THE NAM DOES NOT SHOW A
CLOSED CIRCULATION AND IS LESS BULLISH ON THE MOISTURE RETURN. HAVE
MORE CONFIDENCE IN THE GFS SOLUTION...WHICH IS SUPPORTED BY THE
ECMWF. WILL TREND CLOSE TO THE MAVMOS FOR POPS AND USE A BLEND OF
THE MAV/METMOS FOR TEMPS.
&&
.LONG TERM (SUNDAY THROUGH THURSDAY)...A MID/UPPER TROUGH WITH
EMBEDDED IMPULSES AND DEEP LAYER MOISTURE WILL KEEP AN UNSETTLED
WEATHER PATTERN OVER OUR REGION. LOW LEVEL FLOW WILL CONTINUE TO BE
FROM THE EAST TO NORTHEAST PROVIDING MOSTLY CLOUDY TO CLOUDY
CONDITIONS AT LEAST THROUGH TUESDAY. A SURFACE LOW IS FORECAST TO
DEVELOP OFF THE SOUTHEASTERN U.S. COAST WEDNESDAY AND INTENSIFY AS
IT LIFTS NORTHWARD TOWARD THE NORTH CAROLINA COAST. THIS WILL PULL
DRIER AIR INTO THE REGION WEDNESDAY THROUGH THURSDAY. WENT WITH
CHANCE POPS SUNDAY THROUGH TUESDAY...SLIGHT ON WEDNESDAY AND SILENT
10 POPS ON THURSDAY. TEMPS WILL BE A FEW DEGREES BELOW CLIMO EACH
DAY.
&&
.AVIATION...CLOUD COVER HAS BEEN SLOW TO ERODE TODAY WITH STRATOCU
DECK NOW TRANSITIONING TO CU DECK WITH CIGS WAVERING BETWEEN VFR AND
MVFR. EXPECT THIS TO CONTINUE THROUGH THE AFTERNOON WITH TEMPOS TO
MVFR CONDITIONS. EXPECT SOME DRIER LOW LEVEL AIR OVERNIGHT SO WILL
HAVE MOSTLY VFR THROUGH MIDNIGHT. BY EARLY MORNING...MAY SEE AN
INCREASE IN LOW CLOUDS ONCE AGAIN DROPPING CIGS TO MVFR LEVELS.
CLOUDS EXPECTED TO BURN OFF BY MID MORNING WITH VFR CONDITIONS BY
MIDDAY FRIDAY.
&&
.MARINE...HIGH PRESSURE WILL MOVE FROM THE GREAT LAKES TO THE
NORTHEASTERN STATES AND CANADIAN MARITIMES THE NEXT FEW DAYS
...PERPETUATING THE EASTERLY FLOW OVER THE LOCAL WATERS. THIS FLOW
WILL STRENGTHEN AS LOW PRESSURE DEVELOPS ALONG A STALLED FRONT OVER
THE WESTERN GULF OF MEXICO AND MOVES TOWARD THE NORTHERN GULF COAST
ON SATURDAY. WINDS AND SEAS WILL INCREASE TO EXERCISE CAUTION
CRITERIA AT TIME...ESPECIALLY DURING THE LATE NIGHT AND EARLY
MORNING HOURS.
&&
.FIRE WEATHER...MOIST EAST TO NORTHEAST FLOW WILL CONTINUE FOR NEXT
SEVERAL DAYS. NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 67 87 66 84 66 / 10 10 10 30 30
PANAMA CITY 70 87 67 84 69 / 10 20 20 40 40
DOTHAN 67 85 63 82 62 / 10 10 10 30 30
ALBANY 66 86 64 83 63 / 10 10 10 30 20
VALDOSTA 66 87 65 84 65 / 20 10 10 30 30
CROSS CITY 67 88 66 86 67 / 20 10 10 40 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
JAMSKI/CAMP/BARRY
000
FXUS62 KMLB 181800
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
200 PM EDT THU SEP 18 2008
.DISCUSSION...
...NE SWELLS AND INCREASING THREAT FOR RIP CURRENTS EXPECTED AT THE
BEACHES THIS WEEKEND...
CURRENT WEATHER-TONIGHT...DISSIPATING COLD FRONT SLOWLY MOVING
DOWN THE SOUTHERN HALF OF THE PENINSULA WHILE DRIER MID LEVEL AIR
MASS MOVES INTO NORTHERN PORTION OF CENTRAL FLORIDA. SHORT WAVE
TROUGH SHIFTS INTO THE ATLANTIC WHILE SHORT WAVE RIDGE AND
ASSOCIATED NEGATIVE VORTICITY TRACKS ACROSS THE PANHANDLE AND
NORTHERN FLORIDA. COMBINATION OF THESE TWO FEATURES SHOULD INHIBIT
DEEP CONVECTION DESPITE THE COOLER (-8C) TEMPERATURES ALOFT. LOW
LEVEL RIDGING...SURFACE-850MB...WITH RIDGE AXIS TO THE NORTH WILL
MAINTAIN ONSHORE/NORTHEASTERLY FLOW. CAN EXPECT PERIODS OF MARINE
LAYER STRATOCU AND LIGHT/MODERATE RAIN TO COME ASHORE AND MOVE WELL
INLAND BEFORE LIFTING AND/OR DISSIPATING.
FRI...ALTHOUGH WATER VAPOR LOOP AND MODEL MID/UPPER LEVEL RH FIELDS
ARE SHOWING TRAJECTORY OF DRIER MID/UPPER LEVEL AIR MASS IN DOWN TO
CENTRAL FLORIDA...WENT SLIGHTLY ABOVE MOS POP OVER NORTHERN HALF OF
CWA DUE TO STRENGTHENING ONSHORE FLOW HAVING TO THE POTENTIAL TO
PUSH THE LOW LEVEL MARINE AIR MASS FURTHER INLAND THAN THE MODELS
ARE SUGGESTING.
FRI NIGHT...NAM SHOWS STRONGER LOW LVL NE FLOW ACROSS OUR NRN ZONES
BEHIND THE STATIONARY BOUNDARY WHILE GFS SHOWS WEAKER ONSHORE FLOW
AND SOMEWHAT DRIER AIRMASS OVERALL. WILL LEAN A BIT CLOSER TO THE
NAM AND KEEP LOW SCT RANGE POPS ACROSS NRN/CENTRAL COASTAL SECTIONS
AND SLGT POPS INTERIOR AND FAR SRN COASTAL SECTIONS. STILL THINK
THERE COULD BE SOME LOCALLY HEAVY RAIN ALONG THE VOLUSIA OR BREVARD
COUNTY COAST WHERE ANY CONVERGENT ATLC SHOWER BANDS SET UP OVERNIGHT.
SAT...NAM CONTINUES TO SHOW SHARPER DEFINITION TO SFC BOUNDARY WITH
A NE SURGE OF CLOUDS AND PRECIP ACROSS OUR NRN CWA. GFS SHOWS WEAKER
BOUNDARY AND 12Z MOS GUID HAS LOWERED POPS TO 30-40 PCT RANGE. WILL
STILL TREND FCST SUCH THAT NAM SCENARIO MAY STILL PLAY OUT...AND
WILL KEEP 40-50 PCT POPS WITH HIGHEST CHCS ACROSS N CSTL SECTIONS.
EXPECT NE SWELLS TO INCREASE OVER THE WEEKEND AND PEAK AROUND SUNDAY
WITH THE RISK FOR STRONG AND DANGEROUS RIP CURRENTS AND ROUGH SURF
DEVELOPING AT THE BEACHES BY SAT-SUN.
NO CHANGES AT THIS TIME TO THE EXTENDED FORECAST WHICH KEEPS
ELEVATED POPS INTO MID WEEK AS 12Z GFS SHOWS MID LVL CUT OFF LOW
DEVELOPING NEAR THE MID ATLC TUE-WED OF NEXT WEEK. PREV DISC...
SUN-WED...UPPER RIDGING PATTERN STRENGTHENS WESTWARD BRIEFLY TO
ACROSS THE PENINSULA SUN-SUN NIGHT BEFORE TROUGHING NORTH & WEST IS
FORCED SOUTH & EAST AND IS REINFORCED WITH ADDITIONAL UPPER ENERGY
DIVING SOUTHWARD OVER THE EAST COAST TUE-WED. THIS WILL BE
INTERESTING AS LATEST MEDIUM RANGE MODELS SUGGEST CYCLOGENESIS
DEVELOPING OFF OF THE SOUTHEAST COAST BY EARLY/MIDDLE OF NEXT WEEK.
LIGHT SOUTHEASTERLY LOW-LEVEL FLOW EARLY ON SUN WILL BACK TOWARD
EAST/NORTHEAST FOR THE REMAINDER OF THE PERIOD. ENOUGH MOISTURE WILL
REMAIN POOLED OVER THE AREA TO KEEP 40%-50% POPS IN THE FCST THROUGH
THE EXTENDED.
&&
.AVIATION...MAINLY VFR OUTSIDE OF ISOLD-SCT SHRA/TSRA EXPECTED NEAR
NRN TERMINALS THIS AFTERNOON...KDAB-KMLB OVERNIGHT AND AREA-WIDE ON
SAT.
&&
.MARINE...TONIGHT-FRI...FRESHENING NORTHEAST FLOW AS PRESSURE
GRADIENT INCREASES. EXPECTING 15 TO 20 KNOT FLOW OVER WATER WITH
SEAS BUILDING TO 4 TO 5 FEET. SCEC CONDS DEVELOPING FOR THE
NRN/CENTRAL OFFSHORE LEG LATER TONIGHT INTO FRI MORNING. LONG NE
FETCH WITH WINDS TO 15/15-20 KNOTS AT TIMES INTO THE WEEKEND WILL
ALLOW SEAS TO BUILD TO 4-5 FT NEAR SHORE AND 5-7 FT WELL
OFFSHORE...ESPEC NORTH OF THE CAPE. WINDS AND SEAS SHOULD GRADUALLY
DIMINISH EARLY NEXT WEEK AS FLOW VEERS INTO NEXT TUE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 71 85 72 85 / 30 30 20 50
MCO 71 88 71 88 / 20 40 20 40
MLB 73 86 73 87 / 30 40 20 50
VRB 74 86 72 88 / 30 40 20 50
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...WIMMER
LONG TERM....VOLKMER
000
FXUS62 KTAE 181800
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
200 PM EDT THU SEP 18 2008
.SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...THE EAST COAST
MID/UPPER TROUGH WILL MOVE OFFSHORE WITH SHORT WAVE RIDGING IN ITS
WAKE TONIGHT. ALL OF THE NUMERICAL MODELS DEVELOP A TROUGH ACROSS
THE CENTRAL U.S. ON FRIDAY. THIS TROUGH WILL REMAIN ANCHORED TO OUR
WEST THROUGH THE WEEKEND. A STRONG SURFACE RIDGE CENTERED OVER THE
GREAT LAKES TONIGHT WILL TRANSLATE EASTWARD THROUGH NORTHERN NEW
ENGLAND AND SOUTHEASTERN CANADA. MEANWHILE...AN AREA OF LOW PRESSURE
IS PROGGED TO TAKE SHAPE ALONG A STALLED FRONT OVER THE WESTERN GULF
OF MEXICO AND MOVE TOWARD THE NRN GULF COAST ON SATURDAY. THIS WILL
CREATE AN OVERRUNNING SCENARIO WITH AN INCREASING EASTERLY FLOW IN
THE LOW LEVELS AND SOUTHWESTERLY FLOW ALOFT. THE NAM DOES NOT SHOW A
CLOSED CIRCULATION AND IS LESS BULLISH ON THE MOISTURE RETURN. HAVE
MORE CONFIDENCE IN THE GFS SOLUTION...WHICH IS SUPPORTED BY THE
ECMWF. WILL TREND CLOSE TO THE MAVMOS FOR POPS AND USE A BLEND OF
THE MAV/METMOS FOR TEMPS.
&&
.LONG TERM (SUNDAY THROUGH THURSDAY)...A MID/UPPER TROUGH WITH
EMBEDDED IMPULSES AND DEEP LAYER MOISTURE WILL KEEP AN UNSETTLED
WEATHER PATTERN OVER OUR REGION. LOW LEVEL FLOW WILL CONTINUE TO BE
FROM THE EAST TO NORTHEAST PROVIDING MOSTLY CLOUDY TO CLOUDY
CONDITIONS AT LEAST THROUGH TUESDAY. A SURFACE LOW IS FORECAST TO
DEVELOP OFF THE SOUTHEASTERN U.S. COAST WEDNESDAY AND INTENSIFY AS
IT LIFTS NORTHWARD TOWARD THE NORTH CAROLINA COAST. THIS WILL PULL
DRIER AIR INTO THE REGION WEDNESDAY THROUGH THURSDAY. WENT WITH
CHANCE POPS SUNDAY THROUGH TUESDAY...SLIGHT ON WEDNESDAY AND SILENT
10 POPS ON THURSDAY. TEMPS WILL BE A FEW DEGREES BELOW CLIMO EACH
DAY.
&&
.AVIATION...CLOUD COVER HAS BEEN SLOW TO ERODE TODAY WITH STRATOCU
DECK NOW TRANSITIONING TO CU DECK WITH CIGS WAVERING BETWEEN VFR AND
MVFR. EXPECT THIS TO CONTINUE THROUGH THE AFTERNOON WITH TEMPOS TO
MVFR CONDITIONS. EXPECT SOME DRIER LOW LEVEL AIR OVERNIGHT SO WILL
HAVE MOSTLY VFR THROUGH MIDNIGHT. BY EARLY MORNING...MAY SEE AN
INCREASE IN LOW CLOUDS ONCE AGAIN DROPPING CIGS TO MVFR LEVELS.
CLOUDS EXPECTED TO BURN OFF BY MID MORNING WITH VFR CONDITIONS BY
MIDDAY FRIDAY.
&&
.MARINE...HIGH PRESSURE WILL MOVE FROM THE GREAT LAKES TO THE
NORTHEASTERN STATES AND CANADIAN MARITIMES THE NEXT FEW DAYS
...PERPETUATING THE EASTERLY FLOW OVER THE LOCAL WATERS. THIS FLOW
WILL STRENGTHEN AS LOW PRESSURE DEVELOPS ALONG A STALLED FRONT OVER
THE WESTERN GULF OF MEXICO AND MOVES TOWARD THE NORTHERN GULF COAST
ON SATURDAY. WINDS AND SEAS WILL INCREASE TO EXERCISE CAUTION
CRITERIA AT TIME...ESPECIALLY DURING THE LATE NIGHT AND EARLY
MORNING HOURS.
&&
.FIRE WEATHER...MOIST EAST TO NORTHEAST FLOW WILL CONTINUE FOR NEXT
SEVERAL DAYS. NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 67 87 66 84 66 / 10 10 10 30 30
PANAMA CITY 73 87 67 84 69 / 10 20 20 40 40
DOTHAN 67 85 63 82 62 / 10 10 10 30 30
ALBANY 66 86 64 83 63 / 10 10 10 30 20
VALDOSTA 66 87 65 84 65 / 20 10 10 30 30
CROSS CITY 67 88 66 86 67 / 20 10 10 40 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
JAMSKI/CAMP/BARRY
000
FXUS62 KTBW 181716
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
118 PM EDT THU SEP 18 2008
.SHORT TERM (TONIGHT-SATURDAY)...THERE ARE TWO SLIGHTLY DIFFERENT
MODEL SOLUTIONS FOR THE OUTCOME OF THE WEAKENING FRONTAL BOUNDARY
OVER CENTRAL FLORIDA. NAM SEEMS LIKE THE DRIEST SCENARIO...PUSHING
THE FRONT SOUTH AND OUT OF THE STATE BY FRIDAY EVENING. GFS KEEPS
THE DECAYING BOUNDARY LINGERING OVER SOUTHERN FLORIDA THROUGH
SATURDAY...ALTHOUGH BY THEN SEEMS VERY MUCH DISSIPATED. REGARDLESS
OF THE OUTCOME ALL GUIDANCE BRINGS A DRIER AIRMASS IN THE WAKE OF
THE FRONT THROUGH FRIDAY EVENING WITH A GRADIENT OF POPS FROM THE
COAST THROUGH THE INTERIOR OF 20 TO 50 PERCENT. LATEST WV SAT SHOWS
THE DRY AIRMASS SPREADING OVER THE SOUTHEAST STATES AND ALREADY
FILTERING INTO THE NORTHERN NATURE COAST COUNTIES.
BY SATURDAY...THE BOUNDARY WILL DISSIPATE AND A MOIST AIRMASS WILL
PUSH INTO THE AREA FROM THE EAST...WHICH COMBINED WITH DAYTIME
HEATING AND SEA BREEZE INTERACTIONS WILL BRING INCREASING COVERAGE
OF SHOWERS AND THUNDERSTORMS. 40/50 POPS ARE IN PLACE SATURDAY
AFTERNOON EVERYWHERE.
TEMPERATURES SHOULD REMAIN AROUND CLIMO THROUGH THE FORECAST PERIOD.
&&
LONG TERM (SAT NIGHT-THU)...AN UPPER RIDGE BUILDS IN ACROSS FL AND
THE GULF FROM THE ATLANTIC EARLY IN THE PERIOD AND THEN WEAKENS AND
SHIFTS SOUTHWARD ABOUT MIDWEEK AS AN UPPER TROUGH DEEPENS OVER THE
SE U.S. THESE FEATURES WILL KEEP SW AND WESTERLY FLOW ALOFT THE FA.
AT THE SURFACE...HIGH PRESSURE OVER THE EASTERN SEABOARD ALONG WITH
HIGH PRESSURE OVER THE ATLANTIC WILL MAINTAIN EASTERLY FLOW ACROSS
THE AREA. THE REMNANT FRONTAL BOUNDARY...MAINLY A SWATH OF HIGHER
MOISTURE BY THIS TIME...WILL SHIFT SLOWLY SOUTHWARD OVER THE STATE.
ALTHOUGH THIS WILL HAVE LITTLE CHANGE TO THE FORECAST OF SCATTERED
AFTERNOON AND MAINLY ISOLATED EVENING/NIGHTTIME CONVECTION.
TEMPERATURES WILL GENERALLY RUN FROM AROUND 70 TO THE MID 70S FOR
LOWS TO THE UPPER 80S FOR MAXES. HOWEVER THESE MAY BE BEGIN TO DIP A
DEGREE OR 2 BY THU. THE ONLY UN-CERTAINTY IS AN INVERTED TROUGH
APPROACHING FL AND THEN DEEPENING OFF THE FL-GA-SC COAST BY THE END
OF THE PERIOD. CURRENT THINKING IS THAT THIS WILL NOT HAVE A BIG
IMPACT ON THE FA.
&&
.AVIATION (18/18Z - 19/18Z)...WITH SLIGHTLY DRIER AIR WORKING IN
FROM THE NORTH ALONG WITH NORTHERLY...RATHER THAN THE NW WINDS OF
THE PAST COUPLE OF DAYS...WILL LIMIT AFTERNOON CONVECTION TO VCTS AT
TPA/PIE/SRQ. TO THE SOUTH THE ATMOSPHERE CONTINUES A BIT MORE MOIST
AND WILL REMAIN UNDER NE FLOW. HAVE THEREFORE PLACED TEMPO MVFR IN
THE FMY/RSW TAFS FOR LATE AFTERNOON AND EARLY EVENING. VFR IS
EXPECTED TO PREVAIL OVERNIGHT...HOWEVER ALL LOCATIONS WILL BE UNDER
NE FLOW WITH ENOUGH MOISTURE FOR POSSIBLE PATCHY FOG MAINLY OR SCT
STRATUS ALONG THE COAST.
&&
.MARINE...WEAK FRONTAL BOUNDARY...NEARLY STATIONARY OVER THE EASTERN
GULF...SHOULD LINGER AROUND THE AREA THROUGH FRIDAY AND THEN
DISSIPATE SOUTH OF THE COASTAL WATERS. ISOLATED TO SCATTERED
THUNDERSTORMS ARE EXPECTED...MAINLY IN THE AFTERNOON. WINDS AND SEAS
SHOULD REMAIN BELOW HIGHLIGHT CRITERIA THROUGH THE FORECAST PERIOD.
&&
.FIRE WEATHER...DRIER AIR FILTERING OVER THE NATURE COAST
COUNTIES...BUT HUMIDITIES SHOULD HOLD THROUGH THE WEEKEND WITH NO
FIRE WEATHER CONCERNS ANTICIPATED AT THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 73 88 72 88 / 20 30 20 40
FMY 73 90 72 89 / 20 50 20 50
GIF 72 88 71 88 / 20 40 20 50
SRQ 73 89 72 88 / 20 30 20 40
BKV 69 88 68 87 / 20 20 20 40
SPG 75 88 75 87 / 20 30 20 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/MARINE...AR
LONG TERM/AVIATION...RKR
000
FXUS62 KKEY 181427
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1027 AM EDT THU SEP 18 2008
.DISCUSSION...
ANALYSIS -- THE KEY WEST MORNING UPPER-AIR BALLOON OBSERVATION
REVEALED A MOIST AND UNSTABLY STRATIFIED ATMOSPHERE WITH WEAK
CONVECTIVE INHIBITION AND WEAKLY SHEARED EASTERLY FLOW UP TO ABOUT
14000FT. IT WAS SLIGHTLY DRIER AND MORE STABLE THAN 24 HOURS AGO.
THE LARGE-SCALE PATTERN REMAINS SIMILAR TO 24 HOURS AGO...WITH LIGHT
LOW-LEVEL EASTERLIES GIVING WAY TO LIGHT TO MODERATE UPPER-LEVEL
WESTERLIES. SATELLITE WATER VAPOR CHANNEL IMAGES CLEARLY DEPICT A
SHORT-WAVE TROUGH TRAVERSING THE NORTHEASTERN GULF OF MEXICO AND
NORTHERN FLORIDA THIS MORNING. A REVIEW OF REGIONAL UPPER-AIR
OBSERVATIONS REVEALS THAT THE TROUGH IS BEST DEFINED ABOVE 700MB AND
WEAKENS RAPIDLY WITH DECREASING LATITUDE. HOWEVER...MOVEMENT APPEARS
TO BE TOWARD THE EAST-SOUTHEAST. OVERALL...LARGE-SCALE MID AND UPPER-
TROPOSPHERIC FLOW IS WEAK AND BROADLY CYCLONIC ACROSS THE GULF BASIN
AND FLORIDA PENINSULA -- THERE IS NO DEEP RIDGE PROVIDING
SUPPRESSION.
AFTERNOON FORECASTS -- THE LOCAL THERMODYNAMIC AND KINEMATIC PATTERNS
ARE FAVORABLE FOR ABOVE-AVERAGE SHOWER AND THUNDERSTORM COVERAGE...
PARTICULARLY ALONG AND NORTH OF THE KEYS...AND ESPECIALLY LATER THIS
AFTERNOON AS DIURNAL CIRCULATIONS REACH PEAK INTENSITY. WATERSPOUTS
ARE A POSSIBILITY ONCE AGAIN IN THIS BUOYANT AND WEAKLY SHEARED
ATMOSPHERE. IN ADDITION...LOCALLY HEAVY RAINFALL WILL BE A
POSSIBILITY WITH THE STRONGER...SLOW-MOVING SHOWERS AND
THUNDERSTORMS. THE UPPER TROUGH TO THE NORTH IS A WILDCARD IN THAT IT
POTENTIALLY COULD PROVIDE ADDITIONAL LIFT/DESTABILIZATION ON THE
SYNOPTIC-SCALE BY LATER THIS AFTERNOON OR THIS EVENING.
CURRENT FORECASTS ARE ON TRACK AS CONVECTION IS CURRENTLY ISOLATED IN
COVERAGE. SCATTERED SHOWER AND STORMS ARE LIKELY TO DEVELOP THIS
AFTERNOON. WE MAY INCREASE FIRST-PERIOD RAIN CHANCES BY 10-20 PERCENT
BEFORE NOON.
&&
.MARINE...
NORTHEAST TO EAST BREEZES WILL PREVAIL IN THE 5-10KT RANGE THIS
AFTERNOON. WINDS AND SEAS WILL BE LOCALLY HIGHER IN AND NEAR SHOWERS
AND THUNDERSTORMS. THE SHOWER AND STORM COVERAGE WILL INCREASE
THROUGH THE AFTERNOON HOURS AND BE HIGHEST NEAR THE KEYS AND OVER
THE COASTAL WATERS OF THE GULF OF MEXICO AND FLORIDA BAY. WATERSPOUTS
WILL BE POSSIBLE BENEATH BUILDING CUMULUS/CUMULONIMBUS CLOUD LINES
NEAR THE ISLANDS...WITH THE THREAT INCREASING THROUGH EARLY
AFTERNOON.
&&
.AVIATION...
FOR THE BALANCE OF TODAY...WITH AMPLE MOISTURE AND A LIGHT NORTHEAST
TO EAST LOW LEVEL TRAJECTORY...CLOUD LINE FORMATION WILL THREATEN
VFR CONDITIONS AT THE KEY WEST AND MARATHON TERMINALS. FOR
NOW...WILL MAINTAIN THE INHERITED VICINITY SHOWER IN THE TERMINAL
FORECAST...BUT WILL LIKELY INCLUDE A MVFR TEMPO GROUP FOR OR BEFORE
THE 18Z TAF ISSUANCE.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........KASPER
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......FUENTES
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KMFL 181412
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
1012 AM EDT THU SEP 18 2008
.UPDATE...FRONT STILL PARKED OVER NORTH FLORIDA WITH A LIGHT
NORTHEAST FLOW ACROSS CENTRAL AND SOUTH FLORIDA. 12Z SOUNDING
SHOWS LESS DRY AIR THAN YESTERDAY WITH PWAT`S ABOVE 2 INCHES
AND 200 MB HGT ANALYSIS STILL SHOWS DIVERGENCE ALOFT AND A 55 KNOT
JET MOVING SOUTHEAST OVER THE GULF TOWARDS MARCO ISLAND LATER
TODAY. CONVECTIVE WORKSHEET SHOWED ONLY 41 KNOTS MAX IN A MICROBURST
BUT WITH ALL OF THE ABOVE AND THE FACT AN H5 TROUGH WILL BE MOVING
THROUGH, LOTS OF VERY SLOW MOVING PRECIP INLAND THIS AFTERNOON
WITH THE SEABREEZES ACTIVE AND MANY OUTFLOWS. WITH THIS IN MIND,
ANYPLACE OVER SOUTH FLORIDA MAY GET PRECIP. I AM INCLINED TO RAISE
POPS TO 60 PERCENT AGAINST GUIDANCE BUT WILL NOT FOR THE TERMINALS.
BUT I WILL RAISE TO 60 PERCENT FOR INLAND AREAS.
&&
.PREV DISCUSSION... /ISSUED 402 AM EDT THU SEP 18 2008/
DISCUSSION...WATER VAPOR IMAGERY SHOWS A MID/UPPER LEVEL TROUGH STRETCHING
FROM THE EASTERN SEABOARD SOUTHWEST TO THE NE GULF OF MEXICO. THIS FEATURE
WILL MOVE SE TODAY PROVIDING FOR UPPER LEVEL DIVERGENCE...ALONG WITH
STEEPENING LAPSE RATES. LOW LEVEL WIND FLOW WILL BE NORTHEASTERLY. AM
EXPECTING SCATTERED SHRA/TSRA TO DEVELOP ALONG THE EAST COAST BY LATE
MORNING...THEN SHIFTING/FOCUSING INLAND AND ALONG THE GULF COAST IN
THE AFTERNOON AS A GULF SEA BREEZE DEVELOPS...THOUGH PROBABLY NOT FULLY.
THEN...THE MID/UPPER TROUGH WITH SLIGHTLY INCREASING MID LEVEL FLOW
SHOULD ACT TO PUSH THE CONVECTION THAT DEVELOPS OVER INTERIOR AREAS
BACK TO THE EAST COAST LATE IN THE DAY AND INTO THE EARLY EVENING HOURS.
GIVEN THE UPPER LEVEL DIVERGENCE ALONG WITH SLIGHTLY GREATER INSTABILITY
THIS AFTERNOON...AM EXPECTING SOME OF THE STORMS TO BECOME STRONG...PRODUCING
GUSTY WINDS TO AROUND 50 MPH...SMALL HAIL...FREQUENT LIGHTNING STRIKES
AND HEAVY RAINFALL. THIS ALL WILL BE HIGHLIGHTED IN THE HAZARDOUS WEATHER
OUTLOOK.
SOUTH FL WILL REMAIN SOUTH OF A NEARLY STATIONARY FRONTAL BOUNDARY STRETCHING
FROM NORTH FL TO OFF THE CAROLINA COAST THROUGH THE UPCOMING WEEKEND.
MEANWHILE...A SFC/LOW LEVEL TROUGH OVER THE SE BAHAMAS WILL MOVE SLOWLY
NW AND ACROSS THE AREA LATE FRIDAY THROUGH SATURDAY. AM EXPECTING SCATTERED
SHRA/TSRA TO AFFECT THE AREA DURING THIS PERIOD...WITH SLIGHTLY HIGHER
COVERAGE ALONG THE EAST COAST AT NIGHT COMPARED TO RECENT DUE TO BETTER
LOW LEVEL CONVERGENCE EXPECTED.
NEXT WEEK FEATURES AN INTERESTING WEATHER PATTERN FOR THE EASTERN STATES
WITH BOTH GFS/ECMWF SHOWING ANOTHER MID/UPPER TROUGH MOVING ACROSS THE
SE STATES TO OUR NORTH...THEN CUTTING OFF ACROSS THE CAROLINAS. THE
STATIONARY FRONTAL BOUNDARY TO OUR NORTH WILL REMAIN JUST OFF THE CAROLINA
COAST. GFS/ECMWF ARE IN AGREEMENT SHOWING A SURFACE LOW DEVELOPING ALONG
THE FRONT THU/FRI OFF THE S.E. U.S. COAST...THEN MOVING UP THE EASTERN
SEABOARD NEXT WEEKEND. MEANWHILE...STRONG SURFACE HIGH PRESSURE BUILDS
IN FROM NEW ENGLAND. THE RESULT IS A VERY TIGHT PRESSURE GRADIENT NORTH
OF THE FRONTAL BOUNDARY OFF THE CAROLINA COAST THROUGH MUCH OF NEXT
WEEK...RESULTING IN INCREASING NE WINDS ACROSS A LARGE EXTENT OF
THE WESTERN ATLANTIC TO OUR NORTH. THIS WEATHER PATTERN WILL
MAINLY HAVE RAMIFICATIONS TO OUR MARINE FCST NEXT WEEK...SEE
MARINE DISCUSSION BELOW. WEATHER WISE...WE SHOULD CONTINUE WITH
SCATTERED SHRA/TSRA EACH DAY...AND HAVE KEPT WITH THE NEAR CLIMO
POPS THROUGHOUT THE EXTENDED PERIOD.
MARINE...WINDS WILL REMAIN BELOW 15 KT THROUGH THE FCST PERIOD
WITH SEAS 4 FT OR LESS. DID FOLLOW ALONG WITH THE NOAA WAVEWATCH
MODEL OUTPUT FOR SEAS SAT-MON...AS THE 4 FT SEAS OVER THE LOCAL
ATLANTIC WATERS LOOK REASONABLE...ESPECIALLY PALM BEACH
COAST...AS THERE WILL BE A SMALL FETCH OFF THE CAROLINA/GEORGIA
COAST OVER THE NEXT FEW DAYS. THIS WILL SEND A 7-9 SEC WIND SWELL
INTO THE LOCAL WATERS.
NEXT WEEK COULD FEATURE A POTENTIAL LARGE SWELL EVENT FOR THE
LOCAL ATLANTIC WATERS...AS A LARGE FETCH MAY SET UP JUST OFF THE
EASTERN SEABOARD. ALTHOUGH BOTH GFS/ECMWF AGREE WITH STRENGTHENING
WINDS NORTH OF THE STATIONARY FRONTAL BOUNDARY OFF THE CAROLINA
COAST...THEY DO NOT AGREE ON THE ORIENTATION OF THE FETCH. GFS
SHOWS THE FETCH AIMED AT OUR LOCAL WATERS...WHILE ECMWF HAS WINDS
NORTH OF THE BOUNDARY MORE ENE WITH THE FETCH POINTED NORTH OF OUR
AREA. OF COURSE THIS FETCH ORIENTATION WILL ALL DEPEND ON WHETHER
WE GET SWELLS INTO THE AREA...BUT IF THE GFS SOLUTION IS
CORRECT...A LARGE SWELL EVENT WOULD BE IN THE OFFING NEXT
WEEK...SO STAY TUNED.
FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 75 86 75 / 50 40 50 40
FORT LAUDERDALE 88 77 86 76 / 50 40 50 40
MIAMI 89 77 87 77 / 50 40 50 40
NAPLES 90 72 89 73 / 50 30 40 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...18/GR
SHORT TERM/AVIATION...30/KOB
000
FXUS62 KJAX 181405
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1005 AM EDT THU SEP 18 2008
.UPDATE...AREAS OF FOG AND LOW CLOUDS OVER MAINLY INLAND AREAS S AND
W OF A HOMERVILLE TO JACKSONVILLE TO OCALA LINE. ERN EDGES OF THE
LOW CLOUDS HAVE ERODED AS DAYTIME HEATING UNDER MOSTLY SUNNY CONDS
BEGINS OVER SOME OF THE ERN COUNTIES. SFC MAP SHOWS HIGH PRESSURE
WEDGED IN FROM NC TO GA AT 1022 MB WITH PRIMARILY NELY FLOW OVER THE
FORECAST AREA. LOW LEVEL MOISTURE CONVERGENCE AND SHORTWAVE
TROUGHING OVER THE COASTAL WATERS IS HELPING TO GENERATE SCT
CONVECTION NEAR THE COAST AND MAINLY OFFSHORE OF BRUNSWICK AND
CUMBERLAND ISLAND. THE SHORTWAVE WILL PASS THROUGH THE ERN PARTS OF
THE FORECAST AREA AND WILL BE LEFT WITH LOW LEVEL MOISTURE
CONVERGENCE AND SOME UPPER SUPPORT FROM THE LEFT FRONT QUADRANT OF
AN UPPER LEVEL 250 MB TO GENERATE SCT SHOWERS AND STORMS OVER THE
INLAND AREAS THIS AFTERNOON. HAVE INCREASED POPS AROUND 10% INLAND
AND NEAR THE COAST. TEMPS WERE TWEAKED UP A BIT AS SFC HEATING AND
WATER TEMPS IN THE 80S SHOULD ENABLE HIGHS TO REACH THE MID AND
UPPER 80S ALTHOUGH CLOUDS INLAND AREAS WILL SLOW THE HEATING
PROCESS. DRIER AIR FILTERING IN OVER NRN ZONES WITH DEWPOINTS
POSSIBLY LOWERING INTO THE LOW 60S WILL KEEP POPS ONLY 10-20% FAR N
ZONES. FURTHER S AND W TOWARD SUWANNEE VALLEY AREA...POPS AROUND 40
TO NEAR 50% EXPECTED.
&&
.AVIATION...CLOUDS AND FOG HAVE MADE THE TAF FORECASTS A CHALLENGE
THIS MORNING. CONTINUE TO SEE IMPROVEMENTS TO NEAR MVFR AT JAX AND
VFR AT SSI AND CRG. APPEARS THAT GNV WILL CONTINUE TO HAVE LIFR CIGS
FOR THE NEXT HOUR OR SO. OCNL MVFR CIGS EXPECTED IN THE ABUNDANT RH
BELOW 8 KFT. DAYTIME HEATING AND CONVERGENCE WILL GIVE WAY TO SCT
SHOWERS AND STORMS. WILL MONITOR TRENDS FOR POSSIBLE TEMPO GROUPS
FOR THIS ACTIVITY.
&&
.MARINE...ONLY POSSIBLE CHANGES ANTICIPATED OF THE CWF IS TO ADJUST
TIMING OF INCREASING WINDS AND SEAS FOR TODAY. CURRENT OBS SHOW NELY
WINDS AVERAGING ABOUT 15 KT AND SEAS 3-4 FT.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 84 62 84 62 / 20 10 0 10
SSI 82 70 81 69 / 30 10 20 20
JAX 84 67 83 68 / 40 10 20 20
SGJ 83 71 82 73 / 40 20 30 30
GNV 86 65 85 67 / 40 20 20 10
OCF 89 66 86 67 / 40 30 20 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 7 AM FRIDAY TO 4 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 11 AM FRIDAY TO 1 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.
&&
$$
SHASHY/KERNS
000
FXUS62 KMLB 181357
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
955 AM EDT THU SEP 18 2008
.DISCUSSION...
...LOCALLY HEAVY RAIN POSSIBLE TODAY ESPECIALLY NEAR THE COAST...
...ELEVATED RIP CURRENT RISK THIS WEEKEND AS NORTHEAST SWELLS
IMPACT THE SURF ZONE...
CURRENT WEATHER...LATEST SURFACE ANALYSIS AND FIRST FEW VISIBLE
SATELLITE IMAGES PLACE A WEAK COLD FRONT OVER THE MIDDLE OF FLORIDA
AND HIGH PRESSURE BUILDING DOWN THE PENINSULA FROM THE NORTH.
WEATHER BUOYS AND SURFACE OBSERVATIONS SHOWING NORTHEASTERLY FLOW
ALREADY ESTABLISHED OVER MUCH OF THE FORECAST AREA. ONSHORE FLOW
PUSHING MARINE LAYER STRATOCUMULUS ONSHORE THE COASTAL AREAS WHILE
FLOW JUST ABOVE THE SURFACE IS MOVING CLOUDS NW-SE OVER THE AREA.
THE 9AM WEATHER ROUNDUP SHOWED TEMPERATURES ALREADY IN THE UPPER 70S
TO AROUND 80. THE MORNING ZONES UPDATE WILL MAINLY FRESHEN UP THE
WORDING FOR THE AFTERNOON HOURS AND WIND TRENDS.
&&
.AVIATION...ONSHORE FLOW WILL BRING MVFR STRATOCU AND SHOWERS
ASHORE COASTAL ROUTES AND TAF SITES. DAYTIME HEATING SHOULD DEVELOP
SOME STORMS ACROSS THE INTERIOR.
&&
.MARINE...WEATHER BUOYS RECORDING NORTHEAST WINDS AROUND 10 KNOTS
AND 1 TO 2 FOOT SEAS. LOOKING AT WINDS PICKING UP SOME AS HIGH
PRESSURE BUILDING DOWN THE WATERS SHOULD TIGHTEN THE GRADIENT OVER
WATER BUT NOT MORE THAN 15 KNOTS WORTH FOR THE AFTERNOON HOURS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
WIMMER
000
FXUS62 KTAE 181330 RRA
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
930 AM EDT THU SEP 18 2008
.UPDATE...THE 12Z TAE SOUNDING SHOWED SIGNIFICANT DRYING IN THE
MID/UPPER LEVELS OF THE ATMOSPHERE IN THE WAKE OF THE SHORT WAVE
TROUGH, WHICH WAS LOCATED ALONG THE ATLANTIC COAST. A WEAK VORT LOBE
OVER THE NERN GOMEX TRIGGERED ISOLATED CONVECTION, AND EARLIER
REVISED THE POP GRIDS AND MARINE FCST. THE REGIONAL SURFACE ANALYSIS
DEPICTED A E-W RIDGE OF HIGH PRESSURE CENTERED OVER THE MIDWEST, AND
A STATIONARY FRONT FROM THE CENTRAL GOMEX ACROSS CENTRAL FL AND NEWD
INTO THE ATLANTIC WATERS.
SIMILAR TO WED MORNING, WEDGE OF LOW CIGS AND PATCHY FOG OVER MUCH
OF THE CWA WILL EVENTUALLY ERODE LATER THIS MORNING, WITH SKIES
BECOMING PARTLY CLOUDY. BEST CHANCES FOR AFTN CONVECTION, ALBEIT
ISOLATED, WILL BE OVER OUR ERN ZONES. WILL UPDATE ZONES AFTER 10 AM
TO REMOVE MORNING WORDING.
&&
.AVIATION...IFR/LIFR CIGS WILL SLOWLY BURN OFF THIS MORNING AND GIVE
WAY TO VFR CONDITIONS BY AFTERNOON. WITH THE EASTERLY FLOW BECOMING
MORE ESTABLISHED...EXPECT TO SEE SOME MVFR AND POSSIBLY IFR CIGS
ONCE AGAIN LATE TONIGHT...BUT BETTER VSBY. SHOWER ACTIVITY TO REMAIN
VERY ISOLATED TODAY AND HAVE NOT MENTIONED IN TAFS.
&&
.MARINE...NOCTURNAL ELY SURGE OVER THE ERN LEGS IS SLOWLY WANING,
WITH SPEEDS FROM 10-15 KTS. SPEEDS OVER THE WRN LEGS WERE 5-10 KTS.
SEAS WERE LESS THAN 2 FT WRN LEGS TO 2-3 FT ERN LEGS. BASED ON THESE
TRENDS, WILL MAKE MINOR CHANGES TO THE WINDS AND SEAS FOR THE
MORNING UPDATE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 87 67 87 66 / 10 05 10 10
PANAMA CITY 87 70 86 68 / 10 10 10 10
DOTHAN 84 64 85 63 / 10 05 10 10
ALBANY 85 63 86 64 / 10 05 10 05
VALDOSTA 85 65 86 64 / 20 10 20 10
CROSS CITY 87 67 87 66 / 30 10 20 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
JAMSKI/CAMP
000
FXUS62 KTAE 181330
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
930 AM EDT THU SEP 18 2008
.UPDATE...THE 12Z TAE SOUNDING SHOWED SIGNIFICANT DRYING IN THE
MID/UPPER LEVELS OF THE ATMOSPHERE IN THE WAKE OF THE SHORT WAVE
TROUGH, WHICH WAS LOCATED ALONG THE ATLANTIC COAST. A WEAK VORT LOBE
OVER THE NERN GOMEX TRIGGERED ISOLATED CONVECTION, AND EARLIER
REVISED THE POP GRIDS AND MARINE FCST. THE REGIONAL SURFACE ANALYSIS
DEPICTED A E-W RIDGE OF HIGH PRESSURE CENTERED OVER THE MIDWEST, AND
A STATIONARY FRONT FROM THE CENTRAL GOMEX ACROSS CENTRAL FL AND NEWD
INTO THE ATLANTIC WATERS.
SIMILAR TO WED MORNING, WEDGE OF LOW CIGS AND PATCHY FOG OVER MUCH
OF THE CWA WILL EVENTUALLY ERODE LATER THIS MORNING, WITH SKIES
BECOMING PARTLY CLOUDY. BEST CHANCES FOR AFTN CONVECTION, ALBEIT
ISOLATED, WILL BE OVER OUR ERN ZONES. WILL UPDATE ZONES AFTER 10 AM
TO REMOVE MORNING WORDING.
&&
.AVIATION...IFR/LIFR CIGS WILL SLOWLY BURN OFF THIS MORNING AND GIVE
WAY TO VFR CONDITIONS BY AFTERNOON. WITH THE EASTERLY FLOW BECOMING
MORE ESTABLISHED...EXPECT TO SEE SOME MVFR AND POSSIBLY IFR CIGS
ONCE AGAIN LATE TONIGHT...BUT BETTER VSBY. SHOWER ACTIVITY TO REMAIN
VERY ISOLATED TODAY AND HAVE NOT MENTIONED IN TAFS.
&&
.MARINE...NOCTURNAL ELY SURGE OVER THE ERN LEGS IS SLOWLY WANING,
WITH SPEEDS FROM 10-15 KTS. SPEEDS OVER THE WRN LEGS WERE 5-10 KTS.
SEAS WERE LESS THAN 2 FT WRN LEGS TO 2-3 FT ERN LEGS. BASED ON THESE
TRENDS, WILL MAKE MINOR CHANGES TO THE WINDS AND SEAS FOR THE
MORNING UPDATE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 87 67 87 66 / 10 05 10 10
PANAMA CITY 87 70 86 68 / 10 10 10 10
DOTHAN 84 64 85 63 / 10 05 10 10
ALBANY 85 63 86 64 / 10 05 10 05
VALDOSTA 85 65 86 64 / 20 10 20 10
CROSS CITY 87 67 87 66 / 20 10 20 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
JAMSKI/CAMP
000
FXUS62 KTBW 181236
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
830 AM EDT THU SEP 18 2008
.DISCUSSION...A WEAKENING FRONT IS SLOWLY PUSHING INTO CENTRAL
FLORIDA BRINGING PARTLY CLOUDY SKIES TODAY...BECOMING CLOUDY AT
TIMES. MAIN DRIVING MECHANISM BEHIND AFTERNOON CONVECTION WILL BE
AGAIN SEA BREEZE INTERACTIONS. WITH THE CURRENT FLOW PATTERN...WEAK
TO MODERATE SFC NE WINDS BECOMING SW ALOFT...EXPECT STRONG SEA
BREEZE CIRCULATIONS TO DEVELOP AT BOTH FLORIDA COASTS AND MOVE
INLAND IN THE AFTERNOON HOURS. HIGHER POPS REMAIN IN THE INTERIOR
AND SOUTHERN COUNTIES WITH 50 PERCENT CHANCE OF THUNDERSTORMS. 30 TO
20 POPS ALSO REMAIN IN PLACE FOR COASTAL LOCATIONS...ALTHOUGH ANY
CONVECTION ALONG THE COAST WILL PROBABLY DEVELOP IN THE EARLY
AFTERNOON THEN PUSH INLAND.
CURRENT FORECAST PACKAGE IS ON TRACK AND NO SIGNIFICANT CHANGES ARE
REQUIRED AT THIS TIME.
.PREVIOUS DISCUSSION...
.SHORT TERM (TODAY-SATURDAY)...AS ANTICIPATED A WEAKENING FRONTAL
BOUNDARY HAS SETTLED OVER NORTHERN FLORIDA AND A TROUGH OF LOW
PRESSURE OVER THE SOUTHEASTERN US. MID AND UPPER-LEVEL CLOUDS ARE
STREAMING SOUTHWEST TO NORTHEAST AROUND THE TROUGH AND OVER FLORIDA.
ATMOSPHERIC SOUNDINGS AROUND THE STATE INDICATE NEARLY 2 INCHES OF
PRECIPITABLE WATER FROM MID FLORIDA SOUTHWARD WITH MUCH DRIER
CONDITIONS TO THE NORTH. THE MOIST CONDITIONS ARE EXPECTED TO LINGER
THROUGH AT LEAST SATURDAY WITH ISOLATED TO SCATTERED THUNDERSTORM
ACTIVITY EACH DAY ALONG SEA BREEZE CIRCULATIONS. WITH MID AND
UPPER-LEVEL FLOW OUT OF THE SOUTHWEST AND SURFACE FLOW FROM THE
NORTHEAST...EXPECT STORMS TO FORM MOST FREQUENTLY OVER
CENTRAL/INTERIOR FLORIDA AS WELL AS TO THE SOUTH...INCLUDING
CHARLOTTE AND LEE COUNTIES. TEMPERATURES ARE EXPECTED TO BE NEAR
NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(18/12Z - 19/12Z)...VFR EXCEPT AS NOTED. PATCHY FOG
MAINLY INLAND ALONG WITH SOME SCT STRATUS...NONE IMPACTING TAF
TERMINALS... THIS MORNING. SLIGHTLY DRIER AIR WORKING IN FROM THE
NORTH ALONG WITH NORTHERLY...RATHER THAN THE NW WINDS OF THE PAST
COUPLE OF DAYS...WILL LIMIT AFTERNOON CONVECTION TO VCTS AT
TPA/PIE/SRQ. TO THE SOUTH THE ATMOSPHERE CONTINUES A BIT MORE MOIST
AND WILL REMAIN UNDER NE FLOW. HAVE THEREFORE PLACED PROBE30 MVFR IN
THE FMY/RSW TAFS FOR LATE AFTERNOON AND EARLY EVENING. VFR IS
EXPECTED TO PREVAIL OVERNIGHT...HOWEVER ALL LOCATIONS WILL SEE NE
FLOW WITH ENOUGH MOISTURE FOR PATCHY FOG OR LOW STRATUS.
&&
.MARINE...WEAK FRONTAL BOUNDARY REMAINS NEARLY STATIONARY OVER THE
CENTRAL GULF AND SHOULD LINGER AROUND THE AREA THROUGH THE WEEKEND.
ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED...MAINLY IN THE
AFTERNOON. WINDS AND SEAS SHOULD REMAIN BELOW HIGHLIGHT CRITERIA
THROUGH THE FORECAST PERIOD.
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
DISCUSSION...AR
AVIATION...RKR
000
FXUS62 KMLB 180848
AFDMLB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
448 AM EDT THU SEP 18 2008
.DISCUSSION...
...LOCALLY HEAVY RAIN POSSIBLE TODAY ESPECIALLY NEAR THE COAST...
...ELEVATED RIP CURRENT RISK THIS WEEKEND AS NORTHEAST SWELLS
IMPACT THE SURF ZONE...
TODAY...THE LOW LEVEL FLOW PATTERN WILL TRANSITION TO NORTHEAST
AS A WEAKENING FRONTAL BOUNDARY SAGS INTO THE AREA. THESE EARLY
SEASON BOUNDARIES USUALLY BRING A CONSIDERABLE AMOUNT OF STRATOCU
DUE TO THE FLOW OVER THE WARM ATLANTIC WATERS. THEY ALSO BRING A
THREAT FOR LOCALLY HEAVY RAINFALL NEAR THE COAST IN NARROW
CONVERGENT BANDS.
TROUGH ALOFT WILL KEEP MID LEVELS COOL (-8 TO -9C) BUT REDUCED SFC
HEATING FROM CLOUDS AND INCREASED DRYING FROM THE NORTH WILL LIMIT
THREAT OF (AND CONFIDENCE FOR) SEVERE STORMS. WILL HIGHLIGHT VERY
LOW THREAT FOR DAMAGING WINDS AND LARGE HAIL IN HWO/GHWO. THREAT
FROM C-G LIGHTNING AND HEAVY RAIN APPEARS HIGHER ESP CENTRAL AND
SOUTHERN SECTIONS. THE DEEPER NE FLOW SHOULD BRING THE ATLANTIC
SHOWERS/STORMS ONSHORE DURING THE MORNING...BUT ALSO KEEP STORMS
THAT DEVELOP DURING THE DAY OVER INTERIOR AREAS.
FRI-SAT NIGHT...TROUGHING ALOFT OVER THE CENTRAL CONUS WITH
ASSOCIATED SHORTWAVE ENERGY WILL MIGRATE EASTWARD TOWARDS THE EAST
COAST THROUGH THIS PERIOD. THE UPPER TROUGH AXIS WILL EXTEND
SOUTHWESTWARD TOWARD THE GULF COAST STATES ALLOWING OUR FLOW AT
500 MB TO BECOME SOUTHWESTERLY. SURFACE HIGH PRESSURE ALONG THE
EASTERN SEABOARD WITH CENTER OVER NEW ENGLAND WILL MOVE EASTWARD
OUT INTO THE OPEN ATLC. THIS WILL ALLOW OUR NORTHEAST SURFACE FLOW
TO BECOME MORE EASTERLY DURING THE DAY SAT. DURING THIS TIME DEEP
LAYER MOISTURE WILL SLOWLY RAMP UPWARD INTO THIS WEEKEND. MID-
LEVEL IMPULSES TO THE NORTH...MID-LEVEL TEMPERATURES AT 500 MB
(-7C/-8C) COUPLED WITH A DAILY EAST COAST SEA BREEZE BOUNDARY WILL
PROMOTE SCATTERED SHRA/TSRA ACTIVITY EACH DAY. A FEW STRONG STORMS
ARE PROBABLE OVER EAST CENTRAL FLORIDA BOTH DAYS WITH THE MAIN
THREATS GUSTY DOWNBURST WINDS...SMALL HAIL...CLOUD TO GROUND
LIGHTNING AND LOCALLY HEAVY RAINFALL. ONSHORE FLOW SHOULD MODERATE
HIGHS WITH MIDDLE TO UPPER 80S AREAWIDE.
SUN-WED...UPPER RIDGING PATTERN STRENGTHENS WESTWARD BRIEFLY TO
ACROSS THE PENINSULA SUN-SUN NIGHT BEFORE TROUGHING NORTH & WEST
IS FORCED SOUTH & EAST AND IS REINFORCED WITH ADDITIONAL UPPER
ENERGY DIVING SOUTHWARD OVER THE EAST COAST TUE-WED. THIS WILL BE
INTERESTING AS LATEST MEDIUM RANGE MODELS SUGGEST CYCLOGENESIS
DEVELOPING OFF OF THE SOUTHEAST COAST BY EARLY/MIDDLE OF NEXT
WEEK. LIGHT SOUTHEASTERLY LOW-LEVEL FLOW EARLY ON SUN WILL BACK
TOWARD EAST/NORTHEAST FOR THE REMAINDER OF THE PERIOD. ENOUGH
MOISTURE WILL REMAIN POOLED OVER THE AREA TO KEEP 40%-50% POPS IN
THE FCST THROUGH THE EXTENDED.
&&
.AVIATION... LOW CEILINGS ARE POSSIBLE THRU 13Z ACROSS THE NORTH
INTERIOR AS THE TRANSITION TO NORTHEAST FLOW COMMENCES. EXPECT
COASTAL TERMINALS TO HAVE SOME SHOWERS PUSH INTO THE COAST WITH
MVFR CONDITIONS THIS MORNING. DAYTIME HEATING SHOULD DEVELOP SOME
STORMS ACROSS THE INTERIOR.
&&
.MARINE...INCREASED NORTHEAST FLOW IS FORECAST AS HIGH PRESSURE
STRENGTHENS OVER THE NORTHEAST U.S. WITH GRADIENT TIGHTENING WELL
SOUTHWARD DOWN THE COAST. THE NORTHERN WATERS WILL BE AFFECTED
MOST...STARTING TODAY. CONSIDERABLE MOISTURE CONVERGENCE
ASSOCIATED WITH A WEAKENING FRONTAL BOUNDARY SHOULD PRODUCE AN
AREA OF SHOWERS/STORMS OVER THE WATERS. CAUTION HEADLINE IS A GOOD
BET TONIGHT FOR THE OFFSHORE NORTH LEG AS WINDS REACH 15-20
KNOTS.
FRI-MON...NORTHEAST WINDS AROUND 10-15 KTS (SOUTH)/15-20 KTS
(NORTH) FRI WILL EVENTUALLY DECREASE TO 10-15 KTS FRI NIGHT AND
BECOME MORE EAST/SOUTHEASTERLY EARLY SAT EVENING AND EVENTUALLY
EASTERLY AGAIN SUN AFTERNOON. A NORTHEAST SWELL WILL BUILD ACROSS
THE COASTAL WATERS FRI-SUN WITH SEAS INCREASING 5-6 FT AWAY FROM
THE COAST.
&&
.FIRE WEATHER...WE ARE PROVIDING WEATHER SUPPORT FOR A 30 ACRE
PRESCRIBED BURN IN THE JONATHAN DICKINSON STATE PARK TODAY.
&&
.HYDROLOGY...A SLOW FALL IN RIVER LEVELS IS FORECAST TO CONTINUE
OVER THE MIDDLE ST JOHNS RIVER BASIN INTO THE WEEKEND. THE RIVER
FORECAST POINTS WILL CONTINUE ABOVE FLOOD STAGE INTO NEXT WEEK.
FOR THE LATEST INFO ON ST JOHNS RIVER LEVEL SEE THE RIVER FLOOD
STATEMENT /MIAFLSMLB/.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 85 73 85 71 / 40 20 30 30
MCO 88 71 87 71 / 40 10 30 20
MLB 86 74 86 73 / 50 40 40 30
VRB 87 73 88 73 / 50 40 50 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...KELLY
LONG TERM....SEDLOCK
000
FXUS62 KMFL 180802
AFDMFL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
402 AM EDT THU SEP 18 2008
.DISCUSSION...WATER VAPOR IMAGERY SHOWS A MID/UPPER LEVEL TROUGH STRETCHING
FROM THE EASTERN SEABOARD SOUTHWEST TO THE NE GULF OF MEXICO. THIS FEATURE
WILL MOVE SE TODAY PROVIDING FOR UPPER LEVEL DIVERGENCE...ALONG WITH
STEEPENING LAPSE RATES. LOW LEVEL WIND FLOW WILL BE NORTHEASTERLY. AM
EXPECTING SCATTERED SHRA/TSRA TO DEVELOP ALONG THE EAST COAST BY LATE
MORNING...THEN SHIFTING/FOCUSING INLAND AND ALONG THE GULF COAST IN
THE AFTERNOON AS A GULF SEA BREEZE DEVELOPS...THOUGH PROBABLY NOT FULLY.
THEN...THE MID/UPPER TROUGH WITH SLIGHTLY INCREASING MID LEVEL FLOW
SHOULD ACT TO PUSH THE CONVECTION THAT DEVELOPS OVER INTERIOR AREAS
BACK TO THE EAST COAST LATE IN THE DAY AND INTO THE EARLY EVENING HOURS.
GIVEN THE UPPER LEVEL DIVERGENCE ALONG WITH SLIGHTLY GREATER INSTABILITY
THIS AFTERNOON...AM EXPECTING SOME OF THE STORMS TO BECOME STRONG...PRODUCING
GUSTY WINDS TO AROUND 50 MPH...SMALL HAIL...FREQUENT LIGHTNING STRIKES
AND HEAVY RAINFALL. THIS ALL WILL BE HIGHLIGHTED IN THE HAZARDOUS WEATHER
OUTLOOK.
SOUTH FL WILL REMAIN SOUTH OF A NEARLY STATIONARY FRONTAL BOUNDARY STRETCHING
FROM NORTH FL TO OFF THE CAROLINA COAST THROUGH THE UPCOMING WEEKEND.
MEANWHILE...A SFC/LOW LEVEL TROUGH OVER THE SE BAHAMAS WILL MOVE SLOWLY
NW AND ACROSS THE AREA LATE FRIDAY THROUGH SATURDAY. AM EXPECTING SCATTERED
SHRA/TSRA TO AFFECT THE AREA DURING THIS PERIOD...WITH SLIGHTLY HIGHER
COVERAGE ALONG THE EAST COAST AT NIGHT COMPARED TO RECENT DUE TO BETTER
LOW LEVEL CONVERGENCE EXPECTED.
NEXT WEEK FEATURES AN INTERESTING WEATHER PATTERN FOR THE EASTERN STATES
WITH BOTH GFS/ECMWF SHOWING ANOTHER MID/UPPER TROUGH MOVING ACROSS THE
SE STATES TO OUR NORTH...THEN CUTTING OFF ACROSS THE CAROLINAS. THE
STATIONARY FRONTAL BOUNDARY TO OUR NORTH WILL REMAIN JUST OFF THE CAROLINA
COAST. GFS/ECMWF ARE IN AGREEMENT SHOWING A SURFACE LOW DEVELOPING ALONG
THE FRONT THU/FRI OFF THE S.E. U.S. COAST...THEN MOVING UP THE EASTERN
SEABOARD NEXT WEEKEND. MEANWHILE...STRONG SURFACE HIGH PRESSURE BUILDS
IN FROM NEW ENGLAND. THE RESULT IS A VERY TIGHT PRESSURE GRADIENT NORTH
OF THE FRONTAL BOUNDARY OFF THE CAROLINA COAST THROUGH MUCH OF NEXT
WEEK...RESULTING IN INCREASING NE WINDS ACROSS A LARGE EXTENT OF
THE WESTERN ATLANTIC TO OUR NORTH. THIS WEATHER PATTERN WILL
MAINLY HAVE RAMIFICATIONS TO OUR MARINE FCST NEXT WEEK...SEE
MARINE DISCUSSION BELOW. WEATHER WISE...WE SHOULD CONTINUE WITH
SCATTERED SHRA/TSRA EACH DAY...AND HAVE KEPT WITH THE NEAR CLIMO
POPS THROUGHOUT THE EXTENDED PERIOD.
&&
.MARINE...WINDS WILL REMAIN BELOW 15 KT THROUGH THE FCST PERIOD
WITH SEAS 4 FT OR LESS. DID FOLLOW ALONG WITH THE NOAA WAVEWATCH
MODEL OUTPUT FOR SEAS SAT-MON...AS THE 4 FT SEAS OVER THE LOCAL
ATLANTIC WATERS LOOK REASONABLE...ESPECIALLY PALM BEACH
COAST...AS THERE WILL BE A SMALL FETCH OFF THE CAROLINA/GEORGIA
COAST OVER THE NEXT FEW DAYS. THIS WILL SEND A 7-9 SEC WIND SWELL
INTO THE LOCAL WATERS.
NEXT WEEK COULD FEATURE A POTENTIAL LARGE SWELL EVENT FOR THE
LOCAL ATLANTIC WATERS...AS A LARGE FETCH MAY SET UP JUST OFF THE
EASTERN SEABOARD. ALTHOUGH BOTH GFS/ECMWF AGREE WITH STRENGTHENING
WINDS NORTH OF THE STATIONARY FRONTAL BOUNDARY OFF THE CAROLINA
COAST...THEY DO NOT AGREE ON THE ORIENTATION OF THE FETCH. GFS
SHOWS THE FETCH AIMED AT OUR LOCAL WATERS...WHILE ECMWF HAS WINDS
NORTH OF THE BOUNDARY MORE ENE WITH THE FETCH POINTED NORTH OF OUR
AREA. OF COURSE THIS FETCH ORIENTATION WILL ALL DEPEND ON WHETHER
WE GET SWELLS INTO THE AREA...BUT IF THE GFS SOLUTION IS
CORRECT...A LARGE SWELL EVENT WOULD BE IN THE OFFING NEXT
WEEK...SO STAY TUNED.
&&
.FIRE WEATHER...NO CONCERNS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 75 86 75 / 50 40 50 40
FORT LAUDERDALE 88 77 86 76 / 50 40 50 40
MIAMI 89 77 87 77 / 50 40 50 40
NAPLES 90 72 89 73 / 50 30 40 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
LONG TERM...57/DG
SHORT TERM/AVIATION...65/GS
000
FXUS62 KJAX 180738
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
338 AM EDT THU SEP 18 2008
.SHORT TERM...TODAY THROUGH SATURDAY...
STATIONARY FRONT ACROSS NORTH FLORIDA WILL REMAIN IN PLACE WHILE
HIGH PRESSURE BUILDS TO THE NORTH OF THE REGION. THIS WILL KEEP A
RELATIVELY MOIST LOW LEVEL NORTHEAST FLOW IN PLACE THROUGH THE
PERIOD. SHORTWAVE ALOFT THAT SET OFF CONVECTION YESTERDAY WILL MOVE
EAST OF THE REGION AND WITHOUT THIS TRIGGER OVER THE NEXT COUPLE OF
DAYS WILL SEE POPS MAX OUT IN THE 30-40% RANGE EACH AFTERNOON AND
THUNDERSTORM ACTIVITY SHOULD REMAIN BELOW SEVERE LEVELS. NORTHEAST
WINDS WILL INCREASE TO BREEZY LEVELS ALONG THE COASTAL COUNTIES WITH
15 TO 20 MPH SUSTAINED WINDS AND GUSTS TO 25 MPH AT TIMES. MAX TEMPS
WILL BE HELD DOWN INTO THE LOWER TO MID 80S IN THE COOLER NORTHEAST
FLOW AT THE SURFACE.
.LONG TERM...SUNDAY THROUGH WEDNESDAY...
INVERTED TROF SETTING UP OVER THE WRN ATLC JUST EAST OF THE REGION
AND THIS INCREASED MOIST NORTHEAST FLOW IN CONJUNCTION WITH
SUBTROPICAL JET ALOFT WILL SET THE STAGE FOR LOCALLY HEAVY RAINFALL
FROM CONVERGENT RAIN BANDS SETTING UP ALONG THE COASTAL AREAS.
HAVE CAPPED POPS AT 50% FOR NOW IN THE EXTENDED TIME FRAME BUT WILL
LIKELY NEED TO GO HIGHER AS FORECAST COMES CLOSER. 00Z GFS ENSEMBLE
RUNS STILL SUPPORTING 7 DAY RAINFALL TOTALS OF 2 TO 4 INCHES ALONG
THE COASTAL COUNTIES AND 1 TO 2 INCHES MUCH FURTHER INLAND.
&&
.AVIATION...PREVAILING VLIFR CONTINUES AT JAX THIS MORNING AND
SUSPECT THAT CRG AND GNV MAY FALL TO LIFR/IFR AT SOME POINT DUE TO
LOW CIGS BEFORE SUNRISE. SCT COASTAL SHRA WILL DECREASING THIS
MORNING AS BREEZY NE FLOW FOCUSES AFTN TS DEVELOPMENT INLAND TOWARD
GNV. HAVE JUST MENTIONED VCTS FOR NOW. ANOTHER ROUND OF LOW CIGS AND
FOG EXPECTED TONIGHT.
&&
.MARINE...HOISTED A SCA FOR ALL LEGS FRI AS PGRAD TIGHTENS. SCEC
CONDITIONS WILL CONTINUE TONIGHT INTO TONIGHT. PREVAILING NE FLOW
WILL CONTINUE THROUGH EARLY NEXT WEEK. A MODERATE RISK OF RIP
CURRENTS IS ANTICIPATED FRI.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 84 62 84 62 / 20 0 0 10
SSI 82 70 81 69 / 30 10 20 20
JAX 83 67 83 68 / 30 10 20 20
SGJ 84 71 82 73 / 40 20 30 30
GNV 86 65 85 67 / 30 0 20 10
OCF 88 66 86 67 / 40 0 20 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 7 AM FRIDAY TO 4 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 11 AM FRIDAY TO 1 AM EDT SATURDAY FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.
&&
$$
HESS/ENYEDI
000
FXUS62 KTAE 180709
AFDTAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
245 AM EDT THU SEP 18 2008
.SYNOPSIS....
AT 2 AM EDT...FAIR SKIES DOMINATED WEST HALF WITH CLOUDY SKIES WITH
CIGS AOB 2K EAST HALF OF LOCAL AREA. SATELLITE AND LOCAL OBS SHOW
MID-UPPER LEVEL CLOUDS ARE STREAMING SOUTHWEST TO NORTHEAST AROUND
A TROUGH WHILE LOW STRATUS PERSISTS WITH LOW LEVEL ATLANTIC
COAST WEDGE EAST OF APALACHICOLA RIVER. TEMPS FROM MID 60S NORTH TO
MID 70S COAST. WINDS NE 5-8 MPH.
AT UPPER LEVELS...
LOOKING AT THE BIG PIX...CONUS PATTERN WILL CONTINUE TO DEAMPLIFY
BECOMING QUASI-ZONAL WITH MAIN BELT OF WLYS REMAINING IN CANADA.
MAIN FEATURES ARE TROUGH/LOW JUST OFF W COAST...RIDGE WITH AXIS
FROM ID SEWD TO OH VALLEY...AND LOW OVER HUDSON BAY WITH TROUGH SSW
ALONG EAST COAST. RIDGE EXTENDS FROM GULF OF MEXICO TO THE WESTERN
CARIBBEAN.
CLOSER TO HOME...SATELLITE IMAGERY SHOWS THAT UPPER TROUGH AXIS HAS
PUSHED E OF THE LOCAL AREA WITH NVA/SUBSIDENCE IN ITS WAKE FROM W-E.
DRY AIR CLEARLY WRAPPING AROUND TROUGH AND INTO THE DEEP SOUTH UNDER
WSW FLOW. THIS REFLECTED IN 00Z REGIONAL SOUNDINGS. I.E. JAX...TAE
...FCC AND BMX WITH 1.86...1.54...1.32 AND 0.95 INCH PWAT
RESPECTIVELY. OVER THE NEXT TWO DAYS...WEAK RIDGING WILL BUILD IN
ALOFT AS TROUGH SLOWLY CONTINUES TO SLIDE EAST. 00Z TAE RAOB SHOWS
WINDS ALREADY SHIFTING TO WNW ABOVE 10K FEET.
AT LOWER LEVELS...
PERSISTENT QUASI-STATIONARY FRONTAL ZONE OVER EXTREME OFFSHORE
WATERS OF CWA TO ACROSS DIXIE COUNTY OVERNIGHT INTERACTED WITH LAND
BREEZE AND KICKED OFF SOME STRONG STORMS OVER OFFSHORE LOCAL WATERS
LATE WED NIGHT. FRONT IS EXPECTED TO DRIFT SWD TO OVER N/CENTRAL
FL/GULF LATER TODAY AND THEN STALL AS SEVERAL WAVES RIDE ACROSS IT.
IN WAKE OF FRONT...DEW POINTS DROP OFF STEADILY.
STRONG HIGH PRESSURE WILL CONTINUE BUILDING FROM EAST CENTRAL CANADA
INTO NEW ENGLAND TODAY AND THEN DROP SOUTH ALONG ERN SEABOARD AND
BRIDGE WITH WEAK HIGH PRESSURE OVER THE CAROLINAS TO REINFORCE THE
SURFACE RIDGE DURING THE NEXT FEW DAYS. MODELS AGREE THAT THIS
WILL LEAD TO STRONGER EAST TO NORTHEAST FLOW OVER THE LOCAL REGION
DUE TO A TIGHTENING PRESSURE GRADIENT. HIGHEST POPS ARE EXPECTED TO
BE ALONG EAST COAST WITH POPS NOTICEABLY DECREASING FROM NE-SW.
DRYING OUT OF LOCAL AIRMASS THRU FRI REFLECTED IN MODEL SOUNDINGS.
I.E. 00Z TAE SOUNDING WITH 1.53 IN PWAT AT 06Z THU DROPPING TO 1.05
IN PWAT BY 18Z FRI. THEN MODELS DISAGREE...GFS BRINGS SURFACE LOW
ACROSS NE GULF TO WRN PANHANDLE TRANSPORTING ADDITIONAL MOISTURE
ACROSS CWA. PWAT INCREASES TO 1.61 INCH BY 18Z SAT. HOWEVER...
BELIEVE GFS HAS A PROBLEM WITH CONVECTIVE FEEDBACK. CONVERSELY, NAM
WITH MUCH WEAKER LOW AND KEEPS ASSOCD MOISTURE JUST W OF CWA. WILL
GO ABOUT HALF WAY BETWEEN THE TWO MODELS WHICH MERGES WELL WITH
NEIGHBORING CWA POP GRADIENT.
.SHORT TERM (TODAY THROUGH SATURDAY)...
ATLANTIC WEDGE AGAIN YIELDING LIGHT PATCHY FOG AND LOW STRATUS
THIS MORNING. OTHERWISE...STEERING FLOW WILL BE MOSTLY DRY THROUGH
FRIDAY...WITH JUST THE EASTERNMOST COUNTIES SEEING ISOLATED SHOWERS
DUE TO THE ONSHORE FLOW OFF THE ATLANTIC. HIGH TEMPERATURES EXPECTED
TO BE NEAR CLIMO FOR THE NEXT TWO DAYS. SOME TYPE OF LOW MOVES NE
ACROSS NE GULF AND WILL IMPACT CWA ON SATURDAY.
TODAY AND FRIDAY...10-20 PCT W-E SPLIT. PATCHY FOG LIKELY TONIGHT.
INLAND HIGHS IN MID 80S.
SATURDAY...20-40 PCT N-S POP SPLIT. WITH ADDED CLOUDS...INLAND HIGHS
LOWER TO LOW 80S.
.LONG TERM....SUNDAY THROUGH THURSDAY...
THE SURFACE LOW IN THE WESTERN GULF IS FORECAST BY THE GFS TO
DISSIPATE ON SUNDAY. HOWEVER...UPPER TROUGHING WITH EMBEDDED
IMPULSES ALONG WITH DEEP LAYER MOISTURE WILL KEEP AN UNSETTLED
WEATHER PATTERN OVER OUR REGION. LOW LEVEL FLOW WILL CONTINUE TO BE
FROM THE EAST TO NORTHEAST PROVIDING MOSTLY CLOUDY TO CLOUDY
CONDITIONS AT LEAST THROUGH TUESDAY. A SURFACE LOW IS FORECAST TO
DEVELOP OFF THE SOUTHEAST U.S. COAST WEDNESDAY AND INTENSIFY AS IT
LIFTS NORTHWARD TOWARD THE NORTH CAROLINA COAST. THIS WILL PULL A
DRIER AIRMASS INTO THE REGION WEDNESDAY THROUGH THURSDAY. WENT WITH
CHANCE POPS SUNDAY THROUGH TUESDAY...SLIGHT ON WEDNESDAY AND SILENT
10% POP THURSDAY. TEMPS WILL BE A FEW DEGREES BELOW CLIMO EACH DAY.
&&
.AVIATION...LOW CIGS ARE SPREADING BACK OVER THE REGION UNDER THE NE
FLOW. SURFACE WINDS SHOULD STAY UP AROUND 5 KNOTS OR BETTER THROUGH
DAYBREAK...SO LOW VSBYS ARE NOT AS MUCH OF A CONCERN AS LOW CIGS.
PERIODS OF IFR/LIFR CIGS LOOK GOOD ALL SITES...WITH JUST A TEMPO
IFR CIG TOWARD DAYBREAK AT PFN. SHOULD SEE GRADUAL IMPROVEMENT IN
CIGS TO THE MVFR LEVEL BY 14Z WITH ALL SITES VFR BY 18Z. ONLY A
SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM AT VLD THIS AFTERNOON. TOO
LOW TO EVEN MENTION IN TAF.
&&
.MARINE...MODERATE WINDS AROUND MIDNIGHT ALREADY DROPPING OFF AND
SHOULD CONT TREND DURING THE DAY BEFORE INCREASING ONCE AGAIN THIS
EVENING AS HIGH PRESSURE STRENGTHENS OVER NEW ENGLAND. THIS WILL
INCREASINGLY FAVOR NOCTURNAL ELY SURGES. THE PRESSURE GRADIENT WILL
REMAIN TIGHT THROUGH THE WEEKEND WITH WINDS EXPECTED TO BE NEAR OR
ABOVE EXERCISE CAUTION CRITERIA.
&&
.FIRE WEATHER...NO RED FLAG CONCERNS THROUGH THE END OF THE WORK
WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE 87 67 87 66 / 10 05 10 10
PANAMA CITY 87 70 86 68 / 10 10 10 10
DOTHAN 84 64 85 63 / 10 05 10 10
ALBANY 85 63 86 64 / 10 05 10 05
VALDOSTA 85 65 86 64 / 20 10 20 10
CROSS CITY 87 67 87 66 / 20 10 20 10
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GM...NONE.
&&
$$
BLOCK/BARRY
000
FXUS62 KKEY 180702
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
300 AM EDT THU SEP 18 2008
.DISCUSSION...IN THE MID TO UPPER LEVELS...(700-200 MB)...LATEST
EARLY MORNING SATELLITE IMAGERY OVERLAID WITH STREAMLINE ANALYSIS AS
OF 200 AM...DEPICT THE MAIN AXIS OF AN EARLY COOL SEASON FULL
LATITUDINAL TROUGH CENTERED FROM WESTERN NEW YORK SOUTHWARD TO
FLORIDA. THE KEYS ARE NEAR THE BASE OF THE SYNOPTIC SCALE
TROUGH...BENEATH A COOLER...MOIST...WEAKLY SHEARED AND MORE UNSTABLE
MIDDLE AND UPPER TROPOSPHERE.
IN THE LOWER TO MIDDLE LEVELS...(SURFACE TO 700 MB). LATEST
SATELLITE IMAGERY OVERLAID WITH SURFACE OBSERVATIONS AND ANALYSES AS
OF 200 AM...DETAIL AN EXPANSIVE 1025 MB ANTICYCLONE SITUATED FROM
THE MID ATLANTIC STATES TO THE MISSISSIPPI VALLEY AND SOUTHWARD TO
THE NORTHERN GULF COAST. AHEAD OF THIS...A COLD FRONT IS POSITIONED
WELL OFFSHORE OF THE CAROLINAS SOUTHWESTWARD TO ACROSS NORTH
FLORIDA. ACROSS THE TROPICS...ONLY VERY SUBTLE FEATURES ARE OBSERVED
AND ANALYZED...WITH A WEAK INVERTED TROUGH NEAR THE SOUTHEAST
BAHAMAS...AND ANOTHER WEAK TROPICAL WAVE OVER THE CENTRAL CARIBBEAN
SEA. THE FLORIDA KEYS ARE BENEATH A RATHER MOIST LIGHT TO GENTLE
NORTH TO NORTHEASTERLY FLOW FROM THE SURFACE TO ABOUT 20 KFT.
.CURRENTLY...AS OF 200 AM...SKIES ARE PARTLY TO MOSTLY CLOUDY ACROSS
THE KEYS ISLAND CHAIN AND THE ADJOINING WATERS. AN IBIDEM FROM
YESTERDAYS EARLY MORNING DESCRIPTIONS SHALL BE USED HERE IN THE
SENTENCE THAT FOLLOWS...A TYPICALLY SULTRY MID SEPTEMBER MORNING IS
TAKING SHAPE WITH TEMPERATURES NEAR 80 WITH DEWPOINTS IN THE MIDDLE
AND UPPER 70S. THIS MORNING...C-MAN STATIONS OUTSIDE OF SHOWERS AND
THUNDERSTORMS ALONG THE FLORIDA REEF ARE REGISTERING MOSTLY EAST
WINDS NEAR 10 KNOTS...WITH GUSTS TO 15 KNOTS. ISLAND SENSORS ARE
RECORDING EAST TO SOUTHEAST WINDS BETWEEN 5 AND 10 MPH. KEY WEST
RADAR DETECTS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS
THE ISLANDS AND ADJOINING WATERS FROM THE SEVEN MILE BRIDGE WESTWARD
TO DRY TORTUGAS NATIONAL PARK.
FORECASTS...IN THE MIDDLE AND UPPER LEVELS...TODAY THROUGH
SATURDAY...THE LARGE SCALE TROUGH IS STILL FORECAST BY ALL LARGE
SCALE MODELS TO QUICKLY LIFT OUT TODAY THROUGH
FRIDAY...HOWEVER...BUT THEREAFTER...NO SUBSTANTIAL HEIGHT RISES
SHOULD NOT ALLOW FOR MUCH IN THE WAY OF ADDITIONAL MIDDLE AND UPPER
LEVEL DRYING TO TAKE PLACE.
FOR SATURDAY NIGHT THRU WEDNESDAY...LARGE SCALE MODELS INDICATE A
DEEP MID AND UPPER RIDGE WITH 590 PLUS DM HEIGHTS @ 500 MB PROGGED
TO BUILD FROM EAST OF FLORIDA TO THE CENTRAL ATLANTIC BETWEEN THE
25TH AND 30TH PARALLELS. ANY MID-LEVEL DRYING OVER THE KEYS WILL NOT
NECESSARILY TRANSLATE DOWNWARD ENOUGH TO LESSEN THE CLIMATOLOGICAL
CHANCES FOR RAINFALL.
IN THE LOWER AND MIDDLE LEVELS...SURFACE TO 700 MB...TODAY AND
TONIGHT...FOR TODAY...GIVEN THE SAME THERMODYNAMIC PROFILE EXPECTED
OVER THE KEYS...WITH LIGHT MID AND UPPER LEVEL SHEAR...AND A STORM
MOTION FROM THE MAINLAND...AFTERNOON HOT TOWERS WILL ADVANCE TOWARDS
THE KEYS AND COLLIDE WITH SOLID CUMULUS LINE CONVECTION...ALLOWING
FOR SLIGHTLY HIGHER RAINFALL CHANCES TODAY AND THIS EVENING.
FOR FRIDAY AND SATURDAY...THE AFOREMENTIONED WEAK WAVE AXIS OVER THE
CENTRAL CARIBBEAN IN TANDEM WITH A WEAK RIDGE REMAINING JUST NORTH
OF THE KEYS WILL ALLOW FOR LIGHT EASTERLY BREEZES TO INCREASE TO
BETWEEN 10 AND 15 MPH ON FRIDAY AND SATURDAY. BUT...ONLY A SLIGHT
INCREASE IN THE BREEZE FRIDAY AND SATURDAY WILL PROVIDE LITTLE
RELIEF WITHIN A CONTINUED TYPICALLY HOT AND VERY MUGGY AIRMASS
ACROSS THE KEYS AND ADJOINING WATERS...WITH SLIGHTLY DRIER MID-LEVEL
AIR AND FORECAST SOUNDING PWATS (PRECIPITABLE WATER).
IN TERMS OF RAIN CHANCES...GIVEN LATEST FORECAST SOUNDINGS NEAR
1.75 PWAT FOR FRIDAY AND SATURDAY AS OPPOSED TO NEAR 2.00 INCHES FOR
TODAY...WILL CONTINUE TO FORECAST MIDDLE OF THE ROAD RAIN CHANCES
FOR TODAY AND THIS EVENING AND NEAR NORMAL...30 PERCENT...RAIN
CHANCES FOR FRIDAY AND SATURDAY.
EXTENDED...SUNDAY THROUGH WEDNESDAY...STILL HAVE NO REAL SIGNIFICANT
SYNOPTIC SCALE FEATURES THAT WILL MOVE ALONG SOUTH OF THE WESTERN
ATLANTIC RIDGE THAT WILL JUSTIFY RAISING RAIN CHANCES ABOVE OR BELOW
THE CLIMATOLOGICAL 30 PERCENT...WHICH IS NORMAL AROUND OR JUST AFTER
THE FALL EQUINOX. THEREAFTER...RAIN CHANCES WILL SLOWLY SLIDE BACK
DOWN THROUGH THE FALL AND EARLY WINTER MONTHS. STILL A WHILE TO GO
AT THE END OF THIS WET SEASON.
&&
.MARINE...TODAY THROUGH THE WEEKEND...GENTLE NORTHEAST TO EAST
BREEZES ARE EXPECTED TODAY...WITH GENTLE TO MODERATE NORTHEAST
BREEZES EXPECTED THIS WEEKEND...WITH SCATTERED SHOWERS AND
THUNDERSTORMS. WINDS AND SEAS WILL BE LOCALLY HIGHER IN AND NEAR THE
HEAVIER SHOWERS AND STORMS. WATERSPOUTS WILL BE POSSIBLE BENEATH
BUILDING CUMULUS/CUMULONIMBUS CLOUD LINES NEAR THE ISLANDS FOR AT
LEAST THE NEXT TWO OR THREE DAYS.
&&
.AVIATION...EARLY MORNING SHOWERS WILL BE WELL BEYOND THE VICINITY
OF KEYW. BUT CONDITIONS WILL REMAIN FAVORABLE FOR A LATE MORNING OR
EARLY AFTERNOON CLOUD LINE ALONG THE FLORIDA KEYS...ESPECIALLY THE
LOWER AND MIDDLE KEYS. WILL CARRY VCSH AT BOTH KEYW AND KMTH ISLAND
TERMINALS FROM LATE MORNING ONWARD. BUT EXPLICIT MVFR OR IFR
CONDITIONS WILL NOT BE MENTIONED. EXPECT LIGHT SURFACE WINDS OUT OF
THE EAST/SOUTHEAST EARLY THIS MORNING TO SETTLE INTO AN
EAST/NORTHEASTERLY DIRECTION FOR LATE THIS MORNING THROUGH THE
AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
KEY WEST 87 79 88 79 / 40 30 30 30
MARATHON 89 79 89 79 / 40 30 30 30
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
04/DAF
VISIT US ON THE WEB AT WWW.WEATHER.GOV/KEYWEST
000
FXUS62 KTBW 180629
AFDTBW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
229 AM EDT THU SEP 18 2008
.SHORT TERM (TODAY-SATURDAY)...AS ANTICIPATED A WEAKENING FRONTAL
BOUNDARY HAS SETTLED OVER NORTHERN FLORIDA AND A TROUGH OF LOW
PRESSURE OVER THE SOUTHEASTERN US. MID AND UPPER-LEVEL CLOUDS ARE
STREAMING SOUTHWEST TO NORTHEAST AROUND THE TROUGH AND OVER
FLORIDA. ATMOSPHERIC SOUNDINGS AROUND THE STATE INDICATE NEARLY 2
INCHES OF PRECIPITABLE WATER FROM MID FLORIDA SOUTHWARD WITH MUCH
DRIER CONDITIONS TO THE NORTH. THE MOIST CONDITIONS ARE EXPECTED
TO LINGER THROUGH AT LEAST SATURDAY WITH ISOLATED TO SCATTERED
THUNDERSTORM ACTIVITY EACH DAY ALONG SEA BREEZE CIRCULATIONS. WITH
MID AND UPPER-LEVEL FLOW OUT OF THE SOUTHWEST AND SURFACE FLOW
FROM THE NORTHEAST...EXPECT STORMS TO FORM MOST FREQUENTLY OVER
CENTRAL/INTERIOR FLORIDA AS WELL AS TO THE SOUTH...INCLUDING
CHARLOTTE AND LEE COUNTIES. TEMPERATURES ARE EXPECTED TO BE NEAR
NORMAL THROUGH THE PERIOD.
.LONG TERM (SAT NIGHT-WED)...A REMNANT FRONTAL BOUNDARY WILL REMAIN
IN PLACE ACROSS NORTHERN FLORIDA THROUGH MONDAY WITH SW FLOW ALOFT.
THE BOUNDARY WILL SETTLE SOUTH TO ACROSS CENTRAL FL FOR TUES AND WED
AS AN UPPER TROUGH MOVES INTO THE REGION FROM THE ATLANTIC. THIS
WILL KEEP E/NE FLOW IN PLACE ACROSS THE AREA WITH AFTERNOON SEA
BREEZES DEVELOPING EACH DAY. SCATTERED THUNDERSTORMS WILL DEVELOP
EACH AFTERNOON ALONG THE SEA BREEZE AND OUTFLOW BOUNDARIES WITH
STORMS ENDING GENERALLY BY MIDNIGHT EACH NIGHT. TEMPS WILL REMAIN
WITHIN A DEGREE OR TWO OF NORMAL THROUGH THE PERIOD WITH HIGHS
MAINLY IN THE UPPER 80S AND LOWS AROUND 70 NORTH TO THE LOWER TO MID
70S CENTRAL AND SOUTH.
&&
.AVIATION...VFR EXPECTED AT AREA TERMINALS THROUGH 17Z. AS THE SEA
BREEZE DEVELOPS AND PUSHES INLAND THEREAFTER...MAY HAVE TEMPO MVFR
CIGS AND VSBYS WITH ANY STORMS THAT DEVELOP THROUGH 00Z WITH THE
BEST CHANCES AT THE SOUTHERN TERMINALS. OTHERWISE...VFR THROUGH THE
DAY.
&&
.MARINE...A WEAK BOUNDARY WILL LINGER OVER THE NORTHERN GULF
THROUGH THE WEEKEND WITH ISOLATED THUNDERSTORMS EXPECTED
ESPECIALLY DURING THE EVENING AND OVERNIGHT HOURS. WINDS WILL
INCREASE OVER NORTHERN AND OUTER WATERS IN THE VICINITY OF THE
FRONTAL SYSTEM...ALTHOUGH HAZARDOUS CONDITIONS ARE NOT ANTICIPATED.
&&
.FIRE WEATHER...A MOIST AIRMASS IS EXPECTED TO REMAIN IN PLACE
INTO NEXT WEEK WITH NO FIRE WEATHER HAZARDS EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 89 72 87 72 / 30 20 30 20
FMY 91 73 89 72 / 50 20 50 20
GIF 89 72 87 71 / 50 20 40 20
SRQ 90 72 88 72 / 30 20 30 20
BKV 88 69 87 68 / 30 20 20 20
SPG 88 75 87 75 / 30 20 30 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SHORT TERM/MARINE/FIRE WEATHER...CANTIN
LONG TERM/AVIATION...COLSON
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