FXUS62 KJAX 200758
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
358 AM EDT SAT SEP 20 2008
...PROLONGED NE FLOW EXPECTED...
.SYNOPSIS...MOIST NE FLOW BELOW 800MB CONTINUES TO TRACK A BROAD 
AREA OF CONVECTION INLAND THIS HOUR AFFECTING MAINLY COASTAL CAMDEN 
COUNTY SOUTHWARD TO SAINT JOHNS...EXTENDING AS FAR INLAND AS EASTERN 
BAKER COUNTY. PERIODS OF HEAVY RAINFALL FROM SCATTERED TS HAVE 
PRODUCED HOURLY RAINFALL RATES OF 1-2 INCHES MAINLY ACROSS PORTIONS 
OF DUVAL COUNTY. ELSEWHERE... A STRONG 1032 MB SURFACE HIGH IS 
ADVANCING OFFSHORE OF NEW ENGLAND WITH A WEDGE OF HIGH PRESSURE 
EDGING DOWN THE ATLANTIC SEABOARD INTO SW GA. UPSTREAM AN UPPER 
LEVEL TROUGH WAS JUST W OF THE MS RIVER VALLEY...WITH A STRONG ZONAL 
SOUTHERN STREAM JET OVER THE GULF COAST STATES. 
.SHORT TERM...TODAY THROUGH MON...
AS THE UPPER LEVEL BEGINS TO LIFT NE TODAY...THE JET ON ITS SOUTHERN 
PERIPHERY WILL BEGIN TO TILT MORE SW-NE AS IT APPROACHES OUR ZONES 
FROM THE WEST. MODERATE NE LOW LEVEL FLOW WILL CONTINUE OVER THE 
LOCAL AREA THROUGH THE SHORT TERM PERIOD...BUT BELIEVE WE WILL HAVE 
INCREASING RAIN CHANCES ACROSS ALL AREAS AS UPPER LEVEL FORCING 
INCREASES AND JET ENERGY ADVECTS DEEPER GOMEX MOISTURE OVER OUR AREA 
IN THE UPPER LEVELS. HAVE CONTINUED TO FOCUS THE HIGHEST POPS ALONG 
COAST...WITH DECREASING RAIN CHANCES FARTHER INLAND. LATE SUN INTO 
MON LOOKS INTERESTING AS UPPER LEVEL FORCING MAY INDUCE LOW LEVEL 
CYCLOGENESIS OFFSHORE OF THE FL COAST...WITH A SURGE OF LOW LEVEL 
MOISTURE ADVANCING UP FROM SOUTH FL. FOR NOW HAVE ADVERTISED LIKELY 
POPS FOR OUR SE FL ZONES AND MENTIONED PERIODS OF HEAVY RAINFALL IN 
THE FORECAST. MAIN SHORT TERM CONCERN WITH CONVECTION WILL BE 
TRAINING AREAS OF RAIN THAT MOVE INLAND FROM THE ATLANTIC.
ONSHORE FLOW AND PARTLY TO MOSTLY CLOUDY SKIES WILL HELP KEEP TEMPS 
COMFORTABLE WITH HIGHS ONLY IN THE MID TO LOW 80S AND MINS AS LOW AS 
UPPER 60S INLAND TO MID/UPPER 70S COAST. BREEZY WINDS AROUND 15-20 
MPH WITH GUSTS UP TO 30 MPH OUTSIDE OF CONVECTION CAN BE EXPECTED 
THROUGH THE PERIOD WITH THE HIGHEST MAGNITUDES NEAR THE COAST AND 
INLAND WATERWAYS. AT THIS TIME DO NOT ANTICIPATE A LAKE WIND 
ADVISORY WILL BE NEEDED TODAY...BUT BORDERLINE CONDITIONS WILL EXIST 
FROM MAYPORT SOUTH TO FLAGLER BEACH WHERE SUSTAINED SPEEDS MAY FLIRT 
NEAR 20 MPH BY MIDDAY. 
.LONG TERM...TUE THROUGH SAT...
PERSISTENT ONSHORE FLOW WILL CONTINUE TO CAUSE COASTAL CONCERNS NEXT 
WEEK INCLUDING BEACH EROSION PROBLEMS...ESPECIALLY IF THE GFS HOLDS 
TRUE WHICH INDICATES A VERY STRONG LOW LEVEL NE PRESSURE GRADIENT 
DEVELOPING BY MID-WEEK. HAVE INDICATED A ONSHORE POP FLOW REGIME 
WITH HIGH CHANCES NEAR THE COAST...DECREASING INLAND TO LOW CHANCE 
WITH MAINLY SHRA AND ISOLD TS EXPECTED. MAX TEMPS IN THE LOW TO MID 
80S ARE EXPECTED WITH MINS IN THE MID TO LOW 60S INLAND...TO MID 70S 
COAST. 
&&
.AVIATION...PERSISTENT ONSHORE FLOW IS KEEPING VCSH AND OCCASIONAL
TSRA AT CRG AND JAX AND CIGS ARE MVFR. CIGS ARE VFR AT SSI WHILE
GNV IS NEARLY CLOUD-FREE. SHRA ARE EXPECTED AT JAX AND CRG THRU
THE MORNING BRINGING MVFR CIGS. OTHERWISE VFR WILL PREVAIL AFTER
13Z.
&&
.MARINE...WINDS AND SEAS ARE REMAINING STRONG THIS MORNING AND
WILL EXTEND THE SCA FOR NEAR SHORE WATERS NORTH OF ST. AUGUSTINE.
THE SOUTH LEG APPEARS TO HAVE DECREASED TO SMALL CRAFT EXERCISE
CAUTION CONDITIONS. THE PERSISTENT ONSHORE FLOW HAS MAINTAINED
WINDS NEAR 20 MPH ALONG THE COAST. TIDES AT MAYPORT AND ST.
AUGUSTINE ARE RUNNING 1.5 TO 2 FEET ABOVE NORMAL AND WILL EXTEND
THE COASTAL HAZARD MESSAGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG  82  62  83  65 /  10  10  30  20 
SSI  79  70  80  72 /  30  30  40  40 
JAX  81  68  83  70 /  40  30  40  40 
SGJ  81  72  82  72 /  50  40  40  50 
GNV  84  67  85  68 /  40  30  50  30 
OCF  85  68  86  69 /  40  20  50  30 
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING 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 EARLY THIS MORNING 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.
&&
$$
ENYEDI/TRABERT