004
FXUS62 KJAX 091451
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
951 AM EST TUE FEB 9 2010
PUBLIC UPDATE
SURFACE RIDGE CONTINUES TO NUDGE SOUTHWARD INTO THE
AREA WITH INVERTED TROUGH SLOWLY BREAKING DOWN OVER THE ATLANTIC
COASTAL WATERS. SOUTHERN BRANCH OF THE JET STREAM HAS ALIGNED OVER
THE GULF COAST REGION WITH EMBEDDED DISTURBANCE /SHORTWAVE TROUGH/
CURRENTLY ADVANCING ACROSS THE FLORIDA PANHANDLE. THIS FEATURE AND
ACCOMPANYING WEAK SURFACE LOW WILL ADVANCE ACROSS THE AREA THIS
AFTERNOON. THE ATMOSPHERE IS SLOWLY RECOVERING...WITH LOCAL
DEWPOINTS IN THE 40S AND LOWER 50S. ALTHOUGH THERE WILL BE LARGE
SCALE FORCING THIS AFTERNOON TO WARRANT LIKELY/CATEGORICAL POPS...
NUMERICAL MODELS ARE IN AGREEMENT THERE WILL NOT BE SUFFICIENT
DESTABILIZATION FOR THUNDERSTORM DEVELOPMENT...AT LEAST NOT OVER THE
LOCAL MAINLAND. WILL MAINTAIN JUST SHOWER WORDING WITH RAIN ENDING
WITH DEPARTURE OF AFOREMENTIONED WEATHER FEATURES THIS EVENING.
NORTHWEST WINDS WILL LIKELY QUICKLY INCREASE THIS EVENING FOLLOWING
FRONTAL PASSAGE WITH THE POTENTIAL FOR WIND GUSTS TO NEAR 30 MPH
OVERNIGHT...ESPECIALLY NEAR THE COAST. MAY NEED LAKE WIND ADVISORY
FOR PORTIONS OF THE AREA AND WILL MAKE DECISION WITH THE AFTERNOON
PACKAGE.
WILL INCREASE AFTERNOON POPS TO CATEGORICAL FOR INTERIOR SOUTHEAST
GEORGIA AS WELL AS THE SUWANNEE RIVER VALLEY IN NORTHEAST
FLORIDA. ANTICIPATE MAINLY LIGHT SHOWERS WITH TOTAL PRECIP OF A
QUARTER INCH OR LESS...WITH HIGHEST VALUES ACROSS INTERIOR
SOUTHEAST GEORGIA.
AVIATION
PATCHY GROUND FOG WITH VISIBILITY NEAR 5SM WILL CONTINUE AT KVQQ
THROUGH 15Z...OTHERWISE VFR CONDITIONS ARE FORECAST THROUGH AROUND
18Z. LOW LEVEL WIND SHEAR WILL CONTINUE THROUGH AROUND 15Z AS
SOUTHERLY WINDS NEAR 30 KNOTS AT 1 KFT BLOW OVER MUCH LIGHTER WINDS
AT THE SURFACE. SOUTHERLY WINDS WILL INCREASE DURING THE DAY...
HOWEVER CONSIDERABLE CLOUDINESS SHOULD KEEP BELOW 15 KNOTS. RAIN
SHOWERS WILL INCREASE THIS AFTERNOON AND CEILINGS WILL LIKELY LOWER
INTO MVFR CATEGORY. RAIN WILL END THIS EVENING WITH IFR CIGS
ESTABLISHING ALONG THE FRONT AND FOR A FEW HOURS THEREAFTER.
MARINE
LOCAL COASTAL TROUGH IS BEGINNING TO ADVANCE NORTH WITH SOUTHERLY
WINDS ESTABLISHING ACROSS THE AREA. NOT SURE IF SOUTHERLY WINDS
WILL REACH SCA CONDITIONS IN THE OFFSHORE LEGS THIS AFTERNOON...BUT
WILL LEAVE FOR NOW. MAIN EVENT WILL BE THE INCREASING OFFSHORE WINDS
ESTABLISHING BEHIND FRONTAL PASSAGE THIS EVENING. NUMERICAL MODELS
CONTINUE TO SUGGEST RAPID DEEPENING OF LOW PRESSURE OFF THE COAST OF
MID-ATLANTIC STATES LATE TONIGHT AND INTO WEDNESDAY. THIS COUPLED
WITH STRONG HIGH PRESSURE BUILDING IN FROM THE WEST WILL PRESENT
STRONG PRESSURE GRADIENT ACROSS THE LOCAL AREA. AGREE WITH MIDNIGHT
SHIFT ON UPGRADING SMALL CRAFT ADVISORY CONDS TO GALE WATCH NEARSHORE
AND GALE WARNING OFFSHORE FOR FREQUENT GUSTS TO 35-40 KNOTS BEGINNING
LATER TONIGHT AND CONTINUING THROUGH WED INTO WED NIGHT.
FIRE WEATHER
IN WHAT APPEARS TO BE A SLAM DUNK FOR RED FLAG CONDS ON WEDNESDAY
HAVE UPGRADED WATCH TO A WARNING AS NW WINDS INCREASE TO 15-25 MPH
WITH GUSTS TO 35 MPH AT TIMES IN COMBINATION WITH LOW RH'S IN THE 20
TO 25 PERCENT RANGE.
JAX WATCHES/WARNINGS/ADVISORIES
FL...RED FLAG WARNING FROM 11 AM TO 6 PM EST WEDNESDAY FOR ALACHUA-
BAKER-BRADFORD-CLAY-COLUMBIA-DUVAL-FLAGLER-GILCHRIST-
HAMILTON-MARION-NASSAU-PUTNAM-ST JOHNS-SUWANNEE-UNION.
GA...RED FLAG WARNING FROM 11 AM TO 6 PM EST WEDNESDAY FOR APPLING-
ATKINSON-BACON-BRANTLEY-CHARLTON-CLINCH-COASTAL CAMDEN-
COASTAL GLYNN-COFFEE-ECHOLS-INLAND CAMDEN-INLAND GLYNN-JEFF
DAVIS-PIERCE-WARE-WAYNE.
AM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 1 AM EST
WEDNESDAY 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.
GALE WARNING FROM 1 AM WEDNESDAY TO 1 AM EST THURSDAY 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.
GALE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY EVENING 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.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM EST
WEDNESDAY 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.
PREVIOUS PUBLIC
WEAK UPPER RIDGE EXTEND FROM THE GREAT LAKES
REGION TO OFF THE SE US COAST. UPPER LOW IS DIGGING SSE ACROSS THE N
MS VALLEY. ONE SHORTWAVE PRESENTLY ACROSS E AR WITH ANOTHER SHORTWAVE
OVER KNEW. AT THE SFC...LOW PRESSURE PRESENTLY OVER CENTRAL MS
WITH TRAILING COLD FRONT INTO THE NW GOMEX. THIS FRONT IS PRECEDED
BY A BROKEN LINE OF TSTMS OVER THE GOMEX AND RIGHT ALONG THE GULF
COAST S OF KNEW. COASTAL TROF STILL HOLDING FIRM OVER THE ATLANTIC
WATERS E OF THE AREA WITH SCATTERED SHOWERS ALONG IT. ACROSS THE
IMMEDIATE AREA...MOSTLY CLEAR SKIES PREVAIL OVER MOST OF THE AREA
WITH SOME PATCHY FOG REDUCING VSBYS IN A FEW SPOTS. HIGH
CLOUDINESS IS BEGINNING TO SPREAD INTO THE AREA FROM THE W. EARLY
MORNING TEMPERATURES RANGE FROM THE UPPER 30S TO THE MID 40S
ACROSS THE AREA.
SHORT TERM
RATHER TRICKY FORECAST DURING THE NEXT FEW DAYS. THE
SHORTWAVES ARE PROGGED TO APPROACH THE AREA TODAY WITH 2 DISTINCT
AREAS OF LIFT TRAVERSING THE AREA. THERE ARE DISTINCT DIFFERENCES IN
MODEL HANDLING OF THESE 2 FEATURES ALONG WITH THE COASTAL TROF AND
WEDGE OVER THE SE US. AGREE WITH DAY SHIFT THAT GREATEST THREAT FOR
HEAVIER PRECIP WILL BE OVER THE N AND S PORTIONS OF THE AREA...BUT
HAVE GENERALLY LEFT LIKELY POPS ACROSS THE BOARD BY AFTERNOON DUE TO
UNCERTAINTY AS TO EXACT LOCATION OF PRECIP. BELIEVE THAT MANY AREAS
WILL GET PRECIP AND QPF WILL BE THE GREATEST DIFFICULTY. LINGERING
DRY AIR ASSOCIATED WITH THE WEDGE WILL REDUCE POPS AND WILL KEEP THE
ATMOSPHERE FAIRLY STABLE. HAVE KEPT TSTMS OUT OF THE
FORECAST...ALTHO SOME ACTIVITY MAY MOVE INLAND FROM THE GOMEX OVER
THE S PORTION OF THE AREA.
THE NEXT STORM SYSTEM IS EXPECTED TO DEVELOP RAPIDLY ON THE HEALS
OF THE FIRST. THE SFC LOW IS PROGGED TO TRAVERSE WELL S OF OUR
AREA WITH ONLY LIGHT PRECIP EXPECTED. STILL UNCERTAIN AS TO
LIKELIHOOD OF ANY FROZEN PRECIP WITH THIS FEATURE. TEMPERATURES
WILL BE CLOSE TO FREEZING EARLY FRI MORNING ACROSS THE N 2/3 OF
THE AREA...BUT MOST OF THE PRECIP MAY STAY S OF OUR COUNTY WARNING
AREA UNTIL TEMPERATURES START TO WARM. WILL HOLD OFF FOR NOW ON
MENTIONING THIS IN THE HWO.
LONG TERM
HIGH PRESSURE WILL BUILD OVER THE REGION DURING THE
WEEKEND WITH FREEZING MIN TEMPERATURES OVER PORTIONS OF THE AREA
THRU THE WEEKEND. TEMPERATURES ARE EXPECTED TO WARM UP A BIT LATE
SUN AND MON AHEAD OF ANOTHER COLD FRONT. FOR NOW...FRONT APPEARS
WEAK WITH MINIMAL PRECIP ALONG IT AND SFC LOW WELL TO THE N...
ALTHO A SFC LOW IS PROGGED TO DEVELOP OVER THE NE GOMEX AS THE
FRONT ENTERS THE AREA.
ECZ
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