[top]
000
FXCA62 TJSJ 081951
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
351 PM AST SAT NOV 8 2008
.SYNOPSIS...
LOW LEVEL TROUGH CONTINUING TO MOVE VERY SLOWLY OVER THE LOCAL
AREA...WITH BEST MOISTURE AND DYNAMICS JUST SOUTH OF PUERTO RICO
AT THE MOMENT. EXPECT MOIST AND UNSTABLE CONDITIONS TO PERSIST
UNTIL AT LEAST SUNDAY NIGHT...WITH AREA OF CONCENTRATED SHOWER
ACTIVITY OVER THE COASTAL CARIBBEAN WATERS AND THE SOUTH COAST OF
PUERTO RICO TONIGHT...AND OVER NW PR AND THE MONA CHANNEL BY
SUNDAY AFTERNOON. BY MONDAY MORNING...DRIER AIR WILL BE WORKING
INTO THE AREA FROM THE EAST AND DECREASING THE CHANCES OF RAIN INTO
THE UPCOMING WEEK.
&&
.DISCUSSION...
SATELLITE IMAGERY SHOWS HURRICANE PALOMA MOVING NORTHEASTWARD...AS
A MID TO UPPER LEVEL HIGH OVER THE CENTRAL CARIBBEAN DRIFTS SLOWLY
SOUTHWEST. THIS IS ALLOWING A LOW LEVEL TROUGH ALONG THE EASTERN
PERIPHERY OF THE HIGH TO FINALLY MOVE WESTWARD...BRINGING DEEP
MOISTURE OVER PUERTO RICO. A WEAK SOUTHEASTERLY FLOW AND
CONVERGENT AXIS OVER THE ISLAND IS PRODUCING DEEP CONVECTION AND
ISOLATED AREAS OF VERY HEAVY RAINFALL OVER PORTIONS OF NORTH-
CENTRAL TO NWRN PR. NAM12 HAS A GREAT HANDLE ON TODAYS
PATTERN...INITIALIZING DYNAMICS AND MOISTURE CONVERGENCE VERY
WELL. GUIDANCE FROM THAT MODEL TAKES BEST CONVERGENCE JUST SOUTH
OF SWRN PUERTO RICO BY THIS EVENING...SPLITTING OVERNIGHT WITH A
NORTHERN MAXIMUM OVER THE MONA CHANNEL AND SOUTHERN MAX OVER THE
OPEN CARIBBEAN WATERS WELL SOUTH OF THE ISLANDS. AS THIS
EVOLVES...DRIER AIR...EVIDENT ON MIMIC TPW IMAGERY....WILL BE
ABLE TO BEGIN WORKING INTO THE AREA FROM THE EAST. EXPECT A DRYING
TREND BEGINNING WITH THE VI TONIGHT...SLOWLY WORKING ITS WAY OVER
THE WESTERN PORTION OF THE FA BY LATE SUNDAY. HAVING SAID
THAT...MOISTURE AND DYNAMICS WILL STILL BE AVAILABLE TOMORROW OVER
AT LEAST THE WESTERN HALF OF PR FOR ANOTHER ROUND OF DIURNAL DEEP
CONVECTION.
FOR MONDAY INTO THE REST OF THE UPCOMING WEEK...A TUTT WILL DIG
INTO INTO THE TROPICAL ATLANTIC WITH 700MB REFLECTION ADVECTING
MUCH DRIER AIR ON ITS WESTERN FLANKS INTO THE LOCAL REGION. A FEW
BANDS OF LINGERING MOISTURE ARE POSSIBLE FROM TIME TO TIME ON
MONDAY...BUT IN GENERAL EXPECT A DRY UPCOMING WEEK WITH NO MAJOR SYSTEMS.
&&
.AVIATION...WIDESPREAD MVFR RW/TRW ACROSS N CENTRAL THROUGH NW PR
ARE EXPECTED TO BEGIN TO WEAKEN AFTER 19Z AS THEY SHIFT SLOWLY NW
THROUGH 02Z. THIS WILL AFFECT MAINLY TJBQ WITH PERIODS OF MVFR CIGS
AND OCNL VSBYS...WITH ISOLD IFR CONDS IN TRW POSBL. ISOLD TOPS AOA
40K FT WILL BE SEEN INVOF NW PR THROUGH 02Z. ISOLATED MVFR CIGS ARE
POSBL THROUGH 23Z AT TJMZ AND TJPS. GRADUAL CLEARING FROM THE E IS
THEN EXPECTED OVERNIGHT...WITH VFR CONDS V.I. SITES AND TJSJ
0820-0912Z. ACTIVE WEATHER MAY PERSIST OVERNIGHT ACROSS THE MONA
PASSAGE AND W AND NW COASTAL SECTIONS OF PR AS THIS BAND OF MOISTURE
AND WEATHER GRADUALLY SHIFTS W.
&&
.MARINE...NORTHEASTERLY SWELLS OF ABOUT 4 FEET AT 10 SECONDS ARE
WORKING INTO THE ATLC WATERS AND ANEGADA PASSAGE. WITH A
CONTINUED VERY LIGHT WIND FLOW OVER THE REGION FOR THE LAST
SEVERAL DAYS...THESE SWELLS ARE THE ONLY DOMINANT ENERGY OVER THE
LOCAL WATERS. EXPECT THIS SWELL ENERGY TO MARGINALLY INCREASE...TO
PERHAPS 5 FEET OR SO SUNDAY THROUGH TUESDAY. THEN MID NEXT
WEEK...ANOTHER SET OF NELY ENERGY...AROUND 6-7 FEET AT 10 SECONDS
IS EXPECTED TO AFFECT THE SAME WATERS THROUGH THE END OF THE
FORECAST CYCLE.
&&
.HYDROLOGY...FLOODING WAS EXPERIENCED ON THE RIO FAJARDO IN
EASTERN PR THIS MORNING DUE TO HEAVY RAINS EXPERIENCED LAST 24
HOURS. RADAR ESTIMATES ALSO SHOW AREAS OF 3 TO 4 INCHES OF RAIN
MAY HAVE FALLEN OVERNIGHT OVER THE SOUTHEASTERN PR MUNICIPALITIES
OF MAUNABO AND YABUCOA...WHICH WERE DEVASTATED BY THE HISTORIC
RAIN EVENT OF SEPTEMBER 20-23. GAGES OVER CENTRAL AND WESTERN
PUERTO RICO HAVE SHOWN READINGS REACHING CLOSE TO FLOOD STAGE THE
LAST FEW DAYS...SO HEAVY RAINFALL THIS AFTERNOON IS VERY LIKELY TO
PUSH SMALL STREAMS AND RIVERS INTO FLOOD STAGE THIS AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 76 86 76 86 / 40 40 10 20
STT 75 87 75 86 / 30 40 20 30
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
70/93/
000
FXCA62 TJSJ 081601
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1201 PM AST SAT NOV 8 2008
.UPDATE...THE LOW LEVEL TROUGH HAS SHIFTED INTO THE MONA PASSAGE
OVERNIGHT AND EARLY THIS MORNING...WITH ASSOCIATED CONVERGENCE ON
E SIDE SLIDING WSW OUT OF THE V.I. AND INTO ALL OF PUERTO RICO AND
ADJACENT WATERS BOTH N AND S. CLEARING SKIES AND MORE ISOLATED
SHOWERS EXPECTED ACROSS THE V.I. THIS AFTERNOON...WHILE SCATTERED
TO LOCALLY NUMEROUS SHOWERS AND ISOLATED TSTORMS DEVELOP ACROSS
PR. UPPER LEVEL SHEAR HAS INCREASED PAST 24 HOURS...AND CONVERGENCE
LEADING TO MID LEVEL SUBSIDENCE HAS SHIFTED INTO THE NE CARIB AND
V.I. THUS ATMOSPHERIC CONDITIONS NOT AS UNSTABLE AS PAST 48 HOURS.
ALL THIS WEATHER EXPECTED TO CONTINUE TO SLIDE WSW NEXT 24 HOURS
AND RETURN TO MORE TYPICAL TRADE WIND PATTERN FOR THE FIRST PART
OF THE UPCOMING WEEK. NO CHANGES TO RECENT THINKING.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 87 76 86 76 / 40 40 40 10
STT 87 75 87 75 / 30 30 40 20
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
71/93
000
FXCA62 TJSJ 080957
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
557 AM AST SAT NOV 8 2008
.SYNOPSIS...VERY WEAK AND VARIABLE LOW LEVEL WIND FLOW WILL
PERSIST FOR THE NEXT FEW DAYS. OVER PUERTO RICO...EXPECT SHOWER
AND THUNDERSTORM ACTIVITY TO DEVELOP OVER THE CENTRAL INTERIOR
EACH AFTERNOON...WITH THE COASTS STAYING MAINLY DRY. MAJOR HURRICANE
PALOMA IS LOCATED ACROSS THE WESTERN CARIBBEAN SEA. UPPER LEVEL
HIGH IS LOCATED EAST OF PALOMA.
&&
.DISCUSSION...THE CARIBBEAN ISLANDS ARE INFLUENCE THIS MORNING BY
THREE IMPORTANT FACTORS. THE FIRST ONE...AND THE MOST RELEVANT...IS
MAJOR HURRICANE PALOMA WHICH IS LOCATED NEAR 200 MILES SOUTH OF
CUBA...MOVING NORTHEAST AT 6 KNOTS. PALOMA IS NOW A DANGEROUS
CATEGORY THREE HURRICANE WITH MAXIMUM SUSTAINED WINDS NEAR 110KT.
EAST OF PALOMA IS AN UPPER LEVEL HIGH...WHICH IS EXPECTED TO
WEAKEN AND MOVE FURTHER WEST...AWAY FROM THE LOCAL AREA. AND THE
THIRD SYSTEM IS A WEAK AREA OF LOW PRESSURE CENTERED NORTH OF
EASTERN HISPANIOLA THIS MORNING AND ITS ASSOCIATED TROUGH THAT
EXTENDS SOUTH SOUTHEAST ACROSS PUERTO RICO THIS MORNING. THIS
SYSTEM IS PRODUCING SHOWER AND ISOLATED THUNDERSTORM ACTIVITY
ACROSS THE SURROUNDING WATERS. THIS COMPLEX SCENARIO IS PRODUCING
A WEAK PRESSURE GRADIENT WHICH WILL PERSIST FOR THE NEXT FEW
DAYS...RESULTING IN LIGHT AND VARIABLE WINDS ACROSS THE LOCAL
AREA. HOWEVER...BY MID WEEK...A SURFACE HIGH PRESSURE LOCATED IN
THE NORTH CENTRAL ATLANTIC...IS EXPECTED TO BUILD ACROSS THE
WESTERN ATLANTIC. EAST NORTHEAST TO NORTHEAST WIND FLOW IS THEN
EXPECTED FOR THE LOCAL AREA. THIS WIND FLOW WILL BRING SOME
PATCHES OF MOISTURE TO THE LOCAL AREA BEGINNING ON WEDNESDAY.
HOWEVER...AN UPPER LEVEL TROUGH IS EXPECTED TO MOVE INTO THE
TROPICAL ATLANTIC AND ADVECTS A MUCH DRIER AIR MASS INTO THE
REGION.
&&
.AVIATION...THE LOW LEVEL TROUGH OVER PUERTO RICO IS BRINGING
CONSIDERABLE MOISTURE OVER THE AREA THAT WILL RESULT IN SHOWERS AND
THUNDERSTORMS BEGINNING BY 15-17Z AND CONTINUING THROUGH 09/00Z IN A
FEW PLACES. THIS MOISTURE WILL BRING OCCASIONAL MVFR CONDITIONS TO
TJMZ AND TJBQ WITH MOUNTAIN OBSCURATIONS IN MANY PLACES IN PUERTO
RICO. SHOWERS ARE POSSIBLE OVER THE U.S. VIRGIN ISLANDS AND THE
LEEWARD ISLANDS...BUT THESE WILL HAVE MOSTLY VFR CONDITIONS DURING
THE NEXT 24 HRS...WITH BRIEF MVFR CONDITIONS DUE TO LOW CEILINGS.
EFFECTS FROM THE TROUGH WILL CONTINUE TO BE FELT IN WESTERN PUERTO
RICO ON SUNDAY AS WELL.
&&
.MARINE...TRANQUIL SEAS EXPECTED NEXT 7 DAYS...WITH A VERY LIGHT
WIND FLOW OVER THE LOCAL WATERS. ONLY CHANGE OF NOTE IS A MINOR
NORTHEASTERLY SWELL OF ABOUT 4 FEET AT 10 SECONDS WHICH WILL MOVE
ACROSS THE ATLC WATERS AND ANEGADA PASSAGE DURING THE DAY SUNDAY.
NOT EXPECTING ANY SCA OR HIGH SURF ADVISORY CRITERIA NEXT 7 DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 87 76 86 76 / 40 40 40 10
STT 87 75 87 75 / 40 40 40 20
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
12/71/
000
FXCA62 TJSJ 080354
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1154 PM AST FRI NOV 7 2008
.UPDATE...
SHOWERS AND THUNDERSTORMS ASSOCIATED TO A TROUGH CONTINUED TO
DEVELOP OVER THE EASTERN HALF OF PUERTO RICO. RADAR ESTIMATES WERE
BETWEEN 1 TO 3 INCHES OVER PORTIONS OF EASTERN PUERTO RICO.
INCREASE THE SHOWERS AND COVERAGE FOR MOST OF THE AREA MAINLY
ACROSS THE EASTERN HALF OF THE ISLAND OF PUERTO RICO THROUGH
SATURDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 335 PM AST FRI NOV 7 2008/
SYNOPSIS...A LOW LEVEL TROUGH JUST NORTH OF HISPANIOLA WITH AXIS
EXTENDING SOUTHEASTWARD INTO THE VI HAS REMAINED NEARLY STATIONARY
OVER THE LAST FEW DAYS. THIS TROUGH AXIS IS ON THE EASTERN EDGE OF
AN U/L HIGH PRESSURE SYSTEM OVER THE CENTRAL CARIBBEAN...WHICH
WILL SHIFT SLOWLY WESTWARD AND WEAKEN OVER THE NEXT FEW DAYS AS
HURRICANE PALOMA MOVES NORTH TOWARD CUBA. EXPECT A VERY WEAK
SOUTHEASTERLY WIND FLOW OVER THE NEXT TWO DAYS...WITH SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS OVER THE VI AS WELL AS INTERIOR PUERTO
RICO FOR THE REMAINDER OF THIS AFTERNOON AND SATURDAY AFTERNOON.
THESE STORMS WILL BE VERY SLOW MOVING AND LIKELY TO PRODUCE
ISOLATED AREAS OF HEAVY RAINFALL. A DRIER AIR MASS WILL MOVE OVER
THE LOCAL AREA TUESDAY...AND LIMIT SHOWER ACTIVITY.
DISCUSSION...LATEST SATELLITE IMAGERY SHOWS WEAK LOW LEVEL
CYCLONIC TURNING OVER THE ATLC WATERS JUST NORTH OF HISPANIOLA
THIS AFTERNOON WITH CONVERGENT AXIS EXTENDING SE OVER THE VI. GUIDANCE
HAS BEEN TOO FAST TO BRING THIS TROUGH AXIS WESTWARD ACROSS PR FOR
A DAY OR SO. ALSO OF NOTE IS THAT THE NAM12 MODEL SPINS UP AN LOW
LEVEL VORT SOUTH OF THE ISLAND OVER THE CARIBBEAN WATERS...AND
TAKES THE BULK OF THE MOISTURE WITH IT...SOUTH OF THE AREA THROUGH
SATURDAY. THIS SCENARIO DOES NOT APPEAR TO BE INITIALIZING
WELL...AS BEST MOISTURE APPEARS TO BE NORTH OF THE FORECAST AREA.
WILL GO WITH A VERY WEAK SOUTHEASTERLY FLOW REGIME WITH MOISTURE
ADVECTION CONTINUING TO MOVE WESTWARD...VERY SLOWLY OVER THE
FORECAST AREA THROUGH AT LEAST SUNDAY...MAYBE EVEN MONDAY.
CONSIDERING THE WEAK FLOW...MOISTURE CONVERGENCE WILL CONTINUE TO
SETUP ALONG MOST OF INTERIOR PR AND THE VI WITH ISOLATED AREAS OF
HEAVY RAIN EACH AFTERNOON THROUGH SUNDAY OR MONDAY. SEVERAL RIVERS
ALONG INTERIOR AND WESTERN PUERTO RICO WERE NEAR MINOR FLOOD STAGE
WITH YESTERDAYS HEAVY RAINS...SO EXPECT ADDITIONAL RAINFALL TO
RAPIDLY RESULT IN FLOODING OF RIVERS...STREAMS AND LOW LYING
AREAS.
HEADING INTO TUESDAY NEXT WEEK...A PATTERN CHANGE IS EXPECTED AS A
TUTT DIGS INTO THE TROPICAL ATLANTIC NEAR 50W/20N AND ADVECTS A
MUCH DRIER AIR MASS INTO THE REGION.
AVIATION...SCT AFTERNOON MVFR RW/TRW WILL PERSIST ACROSS PUERTO
RICO THROUGH 23Z WHILE DRIFTING WNW NEAR 5 KT...ISOLD IFR CONDS AND
TOPS AOA 40K FT. WHILE VFR CONDS ARE DOMINATING AT MOST PR SITES
ATTM... PERIODS OF MVFR CONDS ARE LIKELY TO AFFECT TJSJ..TJBQ..AND
TJMZ THRU 23Z. SCT MVFR RW CURRENTLY SPREAD NNW TO SSE ACROSS THE
VIRGIN ISLANDS AND ADJACENT WATERS WILL ALSO INDUCE BRIEF MVFR CONDS
AT TIST AND TISX THROUGH 02Z BEFORE CLEARING OCCURS. THIS MVFR RW
ACTIVITY WILL GRADUALLY SHIFT W THROUGH THE EVENING AND POTENTIALLY
AFFECT TJSJ 00-06Z.
MARINE...TRANQUIL SEAS EXPECTED NEXT 7 DAYS...WITH A VERY LIGHT
WIND FLOW OVER THE LOCAL WATERS. ONLY CHANGE OF NOTE IS A MINOR
NORTHEASTERLY SWELL OF ABOUT 4 FEET AT 10 SECONDS WHICH WILL MOVE
ACROSS THE ATLC WATERS AND ANEGADA PASSAGE DURING THE DAY SUNDAY.
NOT EXPECTING ANY SCA OR HIGH SURF ADVISORY CRITERIA NEXT 7 DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 76 87 76 86 / 60 40 40 40
STT 75 87 75 87 / 50 40 40 40
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
17/10
000
FXCA62 TJSJ 071935
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
335 PM AST FRI NOV 7 2008
.SYNOPSIS...A LOW LEVEL TROUGH JUST NORTH OF HISPANIOLA WITH AXIS
EXTENDING SOUTHEASTWARD INTO THE VI HAS REMAINED NEARLY STATIONARY
OVER THE LAST FEW DAYS. THIS TROUGH AXIS IS ON THE EASTERN EDGE OF
AN U/L HIGH PRESSURE SYSTEM OVER THE CENTRAL CARIBBEAN...WHICH
WILL SHIFT SLOWLY WESTWARD AND WEAKEN OVER THE NEXT FEW DAYS AS
HURRICANE PALOMA MOVES NORTH TOWARD CUBA. EXPECT A VERY WEAK
SOUTHEASTERLY WIND FLOW OVER THE NEXT TWO DAYS...WITH SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS OVER THE VI AS WELL AS INTERIOR PUERTO
RICO FOR THE REMAINDER OF THIS AFTERNOON AND SATURDAY AFTERNOON.
THESE STORMS WILL BE VERY SLOW MOVING AND LIKELY TO PRODUCE
ISOLATED AREAS OF HEAVY RAINFALL. A DRIER AIR MASS WILL MOVE OVER
THE LOCAL AREA TUESDAY...AND LIMIT SHOWER ACTIVITY.
&&
.DISCUSSION...LATEST SATELLITE IMAGERY SHOWS WEAK LOW LEVEL
CYCLONIC TURNING OVER THE ATLC WATERS JUST NORTH OF HISPANIOLA
THIS AFTERNOON WITH CONVERGENT AXIS EXTENDING SE OVER THE VI. GUIDANCE
HAS BEEN TOO FAST TO BRING THIS TROUGH AXIS WESTWARD ACROSS PR FOR
A DAY OR SO. ALSO OF NOTE IS THAT THE NAM12 MODEL SPINS UP AN LOW
LEVEL VORT SOUTH OF THE ISLAND OVER THE CARIBBEAN WATERS...AND
TAKES THE BULK OF THE MOISTURE WITH IT...SOUTH OF THE AREA THROUGH
SATURDAY. THIS SCENARIO DOES NOT APPEAR TO BE INITIALIZING
WELL...AS BEST MOISTURE APPEARS TO BE NORTH OF THE FORECAST AREA.
WILL GO WITH A VERY WEAK SOUTHEASTERLY FLOW REGIME WITH MOISTURE
ADVECTION CONTINUING TO MOVE WESTWARD...VERY SLOWLY OVER THE
FORECAST AREA THROUGH AT LEAST SUNDAY...MAYBE EVEN MONDAY.
CONSIDERING THE WEAK FLOW...MOISTURE CONVERGENCE WILL CONTINUE TO
SETUP ALONG MOST OF INTERIOR PR AND THE VI WITH ISOLATED AREAS OF
HEAVY RAIN EACH AFTERNOON THROUGH SUNDAY OR MONDAY. SEVERAL RIVERS
ALONG INTERIOR AND WESTERN PUERTO RICO WERE NEAR MINOR FLOOD STAGE
WITH YESTERDAYS HEAVY RAINS...SO EXPECT ADDITIONAL RAINFALL TO
RAPIDLY RESULT IN FLOODING OF RIVERS...STREAMS AND LOW LYING
AREAS.
HEADING INTO TUESDAY NEXT WEEK...A PATTERN CHANGE IS EXPECTED AS A
TUTT DIGS INTO THE TROPICAL ATLANTIC NEAR 50W/20N AND ADVECTS A
MUCH DRIER AIR MASS INTO THE REGION.
&&
.AVIATION...SCT AFTERNOON MVFR RW/TRW WILL PERSIST ACROSS PUERTO
RICO THROUGH 23Z WHILE DRIFTING WNW NEAR 5 KT...ISOLD IFR CONDS AND
TOPS AOA 40K FT. WHILE VFR CONDS ARE DOMINATING AT MOST PR SITES
ATTM... PERIODS OF MVFR CONDS ARE LIKELY TO AFFECT TJSJ..TJBQ..AND
TJMZ THRU 23Z. SCT MVFR RW CURRENTLY SPREAD NNW TO SSE ACROSS THE
VIRGIN ISLANDS AND ADJACENT WATERS WILL ALSO INDUCE BRIEF MVFR CONDS
AT TIST AND TISX THROUGH 02Z BEFORE CLEARING OCCURS. THIS MVFR RW
ACTIVITY WILL GRADUALLY SHIFT W THROUGH THE EVENING AND POTENTIALLY
AFFECT TJSJ 00-06Z.
&&
.MARINE...TRANQUIL SEAS EXPECTED NEXT 7 DAYS...WITH A VERY LIGHT
WIND FLOW OVER THE LOCAL WATERS. ONLY CHANGE OF NOTE IS A MINOR
NORTHEASTERLY SWELL OF ABOUT 4 FEET AT 10 SECONDS WHICH WILL MOVE
ACROSS THE ATLC WATERS AND ANEGADA PASSAGE DURING THE DAY SUNDAY.
NOT EXPECTING ANY SCA OR HIGH SURF ADVISORY CRITERIA NEXT 7 DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 76 87 76 86 / 40 20 30 30
STT 75 87 75 87 / 50 40 40 30
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
70/93/
000
FXCA62 TJSJ 071608
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1208 PM AST FRI NOV 7 2008
.UPDATE...MOISTURE CONVERGENCE ALONG AND E OF LLVL TROUGH AXIS
ACROSS THE AREA CONTINUES TO PRODUCE A MOIST AND UNSTABLE
ENVIRONMENT FOR ISOLATED DEEP CNVTN TODAY. DIURNAL FORCING ACROSS
PR...AND GRADUALLY INCREASING MOISTURE SHOULD AGAIN LEAD TO ACTIVE
WEATHER ACROSS THE INTERIOR AND W...WITH MOISTURE ADVECTION
ASSOCIATED WITH DRIFTING TROUGH ALLOWING FOR AFTERNOON WEATHER
ALSO ACROSS ERN SECTIONS AS WELL. HAVE MADE SLIGHT ADJUSTMENTS TO
FORECAST TO INCREASE RAIN CHANCES FOR THE E HALF OF THE
ISLAND...BUT OTHERWISE...NO CHANGES TO SYNOPTIC REASONING.
MOISTURE FORECAST TO DECREASE ...BUT DRIFT W TO SW ACROSS ENTIRE
AREA FOR SATURDAY.
&&
.PREV DISCUSSION... /ISSUED 527 AM AST FRI NOV 7 2008/
SYNOPSIS... VERY WEAK AND VARIABLE LOW LEVEL WIND FLOW WILL
PERSIST FOR THE NEXT FEW DAYS. OVER PUERTO RICO...EXPECT SHOWER
AND THUNDERSTORM ACTIVITY TO DEVELOP OVER THE CENTRAL INTERIOR
EACH AFTERNOON...WITH THE COASTS STAYING MAINLY DRY. THE VI AND
SURROUNDING WATERS WILL BE WETTER AND MORE UNSTABLE AS A LOW LEVEL
TROUGH EXTENDING FROM A LOW PRESSURE CENTER JUST NORTH OF
HISPANIOLA WILL PRODUCE DEEP CONVECTION WITH THE POTENTIAL FOR
ISOLATED AREAS OF HEAVY RAIN...OVER THE NEXT FEW DAYS. HURRICANE
PALOMA IS LOCATED ACROSS THE SOUTHWESTERN CARIBBEAN SEA. UPPER
LEVEL HIGH IS LOCATED EAST OF PALOMA.
DISCUSSION...THE CARIBBEAN ISLANDS ARE INFLUENCE THIS MORNING BY
THREE IMPORTANT FACTORS. THE FIRST ONE...AND THE MOST RELEVANT...IS
HURRICANE PALOMA WHICH IS LOCATED NEAR 300 MILES SOUTH OF
CUBA...MOVING NORTH AT 8 KNOTS. EAST OF PALOMA IS AN UPPER LEVEL
HIGH...RESULTING IN DRY AIR ACROSS MUCH OF THE EASTERN CARIBBEAN.
AND THE THIRD SYSTEM IS THE LOW PRESSURE CENTERED NORTH OF EASTERN
HISPANIOLA THIS MORNING AND ITS ASSOCIATED TROUGH THAT EXTENDS
SOUTH SOUTHEAST ACROSS THE U.S. VIRGIN ISLANDS. THIS SYSTEM IS
PRODUCING SHOWER AND ISOLATED THUNDERSTORM ACTIVITY ACROSS THE
U.S. VIRGIN ISLANDS AND SURROUNDING WATERS. OVER PUERTO
RICO...MODERATED SHOWERS WERE STARTING TO MOVE ACROSS THE
NORTHEAST SECTIONS OF PUERTO RICO. THIS COMPLEX SCENARIO IS
PRODUCING A WEAK PRESSURE GRADIENT WHICH WILL PERSIST FOR THE NEXT
FEW DAYS...RESULTING IN LIGHT AND VARIABLE WINDS ACROSS THE LOCAL
AREA. FOR THE MORNING FORECAST PACKAGE...A BLEND BETWEEN NAM12 AND
GFS40 WAS MADE TO ADJUST THE WIND FIELD ACROSS THE LOCAL
ISLANDS...IN ACCORDANCE TO THE LATEST SATELLITE IMAGES AND SURFACE
OBSERVATIONS.
AVIATION...A WEAK TROUGH IS DRIFTING SLOWLY THROUGH THE FORECAST
AREA TRIGGERING SHOWERS AND THUNDERSTORMS. AT 09Z MOST ACTIVITY WAS
NORTH OF LUQUILLO AND SOUTH OF SAINT CROIX. THIS WILL LAST PERHAPS
AS LATE AS 14Z. OTHER SHOWERS WITH BRIEF MVFR CONDITIONS HAVE MOVED
INTO LUQUILLO AND FAJARDO...CEIBA AND NAGUABO BUT WILL DISSIPATE BY
12Z. LATER IN THE DAY...BETWEEN 17-20Z SHOWERS AND THUNDERSTORMS
WILL DEVELOP OVER THE CORDILLERA CENTRAL OF PUERTO RICO AND SPREAD
NORTHWEST...OBSCURING THE MOUNTAINS AND BRINGING OCCASIONAL MVFR
CONDITIONS TO TJMZ AND TJBQ. THESE CONDITIONS WILL BE INTERMITTENT
AND MAY LAST THROUGH 08/00Z...BEFORE DISSIPATING. WINDS WILL BE
LIGHTER THAN USUAL IN THE AREA DUE TO WEAK PRESSURE GRADIENTS.
MARINE...VERY TRANQUIL MARINE CONDITIONS ARE EXPECTED THROUGH THE
NEXT 7 DAYS AS VERY WEAK WINDS AND NO SIGNIFICANT SWELLS ARE
EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 87 76 87 76 / 20 40 20 30
STT 87 75 87 75 / 50 50 40 40
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
70/93
000
FXCA62 TJSJ 070927
AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
527 AM AST FRI NOV 7 2008
.SYNOPSIS... VERY WEAK AND VARIABLE LOW LEVEL WIND FLOW WILL
PERSIST FOR THE NEXT FEW DAYS. OVER PUERTO RICO...EXPECT SHOWER
AND THUNDERSTORM ACTIVITY TO DEVELOP OVER THE CENTRAL INTERIOR
EACH AFTERNOON...WITH THE COASTS STAYING MAINLY DRY. THE VI AND
SURROUNDING WATERS WILL BE WETTER AND MORE UNSTABLE AS A LOW LEVEL
TROUGH EXTENDING FROM A LOW PRESSURE CENTER JUST NORTH OF
HISPANIOLA WILL PRODUCE DEEP CONVECTION WITH THE POTENTIAL FOR
ISOLATED AREAS OF HEAVY RAIN...OVER THE NEXT FEW DAYS. HURRICANE
PALOMA IS LOCATED ACROSS THE SOUTHWESTERN CARIBBEAN SEA. UPPER
LEVEL HIGH IS LOCATED EAST OF PALOMA.
&&
.DISCUSSION...THE CARIBBEAN ISLANDS ARE INFLUENCE THIS MORNING BY
THREE IMPORTANT FACTORS. THE FIRST ONE...AND THE MOST RELEVANT...IS
HURRICANE PALOMA WHICH IS LOCATED NEAR 300 MILES SOUTH OF
CUBA...MOVING NORTH AT 8 KNOTS. EAST OF PALOMA IS AN UPPER LEVEL
HIGH...RESULTING IN DRY AIR ACROSS MUCH OF THE EASTERN CARIBBEAN.
AND THE THIRD SYSTEM IS THE LOW PRESSURE CENTERED NORTH OF EASTERN
HISPANIOLA THIS MORNING AND ITS ASSOCIATED TROUGH THAT EXTENDS
SOUTH SOUTHEAST ACROSS THE U.S. VIRGIN ISLANDS. THIS SYSTEM IS
PRODUCING SHOWER AND ISOLATED THUNDERSTORM ACTIVITY ACROSS THE
U.S. VIRGIN ISLANDS AND SURROUNDING WATERS. OVER PUERTO
RICO...MODERATED SHOWERS WERE STARTING TO MOVE ACROSS THE
NORTHEAST SECTIONS OF PUERTO RICO. THIS COMPLEX SCENARIO IS
PRODUCING A WEAK PRESSURE GRADIENT WHICH WILL PERSIST FOR THE NEXT
FEW DAYS...RESULTING IN LIGHT AND VARIABLE WINDS ACROSS THE LOCAL
AREA. FOR THE MORNING FORECAST PACKAGE...A BLEND BETWEEN NAM12 AND
GFS40 WAS MADE TO ADJUST THE WIND FIELD ACROSS THE LOCAL
ISLANDS...IN ACCORDANCE TO THE LATEST SATELLITE IMAGES AND SURFACE
OBSERVATIONS.
&&
.AVIATION...A WEAK TROUGH IS DRIFTING SLOWLY THROUGH THE FORECAST
AREA TRIGGERING SHOWERS AND THUNDERSTORMS. AT 09Z MOST ACTIVITY WAS
NORTH OF LUQUILLO AND SOUTH OF SAINT CROIX. THIS WILL LAST PERHAPS
AS LATE AS 14Z. OTHER SHOWERS WITH BRIEF MVFR CONDITIONS HAVE MOVED
INTO LUQUILLO AND FAJARDO...CEIBA AND NAGUABO BUT WILL DISSIPATE BY
12Z. LATER IN THE DAY...BETWEEN 17-20Z SHOWERS AND THUNDERSTORMS
WILL DEVELOP OVER THE CORDILLERA CENTRAL OF PUERTO RICO AND SPREAD
NORTHWEST...OBSCURING THE MOUNTAINS AND BRINGING OCCASIONAL MVFR
CONDITIONS TO TJMZ AND TJBQ. THESE CONDITIONS WILL BE INTERMITTENT
AND MAY LAST THROUGH 08/00Z...BEFORE DISSIPATING. WINDS WILL BE
LIGHTER THAN USUAL IN THE AREA DUE TO WEAK PRESSURE GRADIENTS.
&&
.MARINE...VERY TRANQUIL MARINE CONDITIONS ARE EXPECTED THROUGH THE
NEXT 7 DAYS AS VERY WEAK WINDS AND NO SIGNIFICANT SWELLS ARE
EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 87 76 87 76 / 20 40 20 30
STT 87 75 87 75 / 50 50 40 40
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&
$$
12/71/
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