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000 FXUS62 KJAX 231118 AAA AFDJAX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSONVILLE FL 618 AM EST MON NOV 23 2009 .UPDATE...ZONES WERE UPDATED FOR DENSE FOG ADVISORY. .SHORT TERM (MON-WED)...A QUASI-STATIONARY FRONT WAS JUST SOUTH OF THE I-10 CORRIDOR AND CONNECTED TO A BROAD LOW OFFSHORE NE FL EARLY THIS MORNING. CONSIDERABLE LOW CLOUDS AND FOG NEAR AND NORTH OF THE BOUNDARY WHILE PATCHY DENSE FOG WAS FORMING SOUTH OF THE BOUNDARY. A FEW AREAS NORTH OF THE BOUNDARY MAY STILL GET PATCHY DENSE FOG DUE TO THE WET GROUNDS FROM THE RECENT RAIN SO HAVE MENTION OF PATCHY DENSE FOG EVERYWHERE EARLY THIS MORNING. WEAK ISENTROPIC LIFT IN THE AREA MAY ALSO RESULT IN OCCASIONAL LIGHT DRIZZLE THROUGH THE EARLY MORNING HOURS. AS THE LOW OFFSHORE LIFTS NE...THE FRONT WILL MOVE SOUTH STALLING ACROSS CENTRAL FL THIS AFTERNOON. WHILE THE PATCHY DENSE FOG WILL LIFT BY MID MORNING...MODELS INDICATE LOW CLOUDS LINGERING THROUGH MOST OF THE MORNING ACROSS NE FL AND MUCH OF DAY ACROSS SE GA. THIS WILL PLAY A MAJOR ROLE IN TEMPS...SE GA LIKELY REMAINING IN THE MID 60S WHILE N CNTL FL WILL BE NEAR 80 AS BREAKS IN THE CLOUDINESS ARE EXPECTED THIS AFTERNOON. NOT MUCH CHANGE IS EXPECTED TUESDAY. WILL CONTINUE TO SEE CONSIDERABLE CLOUDINESS ACROSS THE AREA AS FRONT REMAINS NEARLY STATIONARY TO THE SOUTH WITH WIDESPREAD LOW CLOUDS AND PATCHY LATE NIGHT AND EARLY MORNING DENSE FOG. THIS IS DUE TO A SHALLOW COOL AND MOIST LAYER BEING TRAPPED BELOW A LOW LEVEL INVERSION. SHORT WAVE ENERGY WILL BEGIN TO RIDE THE BOUNDARY TUE NITE-WED RESULTING IN AMPLIFICATION OF COASTAL TROUGH OFFSHORE. THIS RESULTS IN CHC POPS NE FL AND SLGT CHC FOR SE GA. .LONG TERM (THU-SUN)...A DEEP UPPER LEVEL TROUGH...AN APPROACHING WEAK SFC FRONT AND THE INVERTED TROUGH OFFSHORE OF THE SE ATLANTIC COAST WILL PROGRESS DOWNSTREAM OF THE REGION LATE THU. HAVE KEPT LOW POPS IN FOR EASTERN AREAS ON THANKSGIVING BUT THAT IS MORE LIKELY TO BE MAINLY IN THE MORNING. A TROUGH DEEPENS ALONG THE EASTERN U.S. RESULTING IN STRONG COLD AIR ADVECTION BEGINNING OVER THE CWA FRI WITH TEMPS FALLING BELOW CLIMO VALUES FOR THE WEEKEND. EXPECT MINS IN THE 30S WELL INLAND/40S COAST WITH MAXES IN THE 60S UNDER MOSTLY CLEAR SKIES SAT AND SUN. && .AVIATION...IFR CIGS ARE MAINLY CONFINED OVER SOUTHEAST GEORGIA AT THIS TIME BUT THESE CIGS ARE GRADUALLY WORKING THEIR WAY INTO NE FL. A NARROW AREA OF LOWER MOISTURE AND GENERALLY WEAK ISENTROPIC ASCENT APPEARS TO BE ALLOWING SOME TEMPO VFR WHICH WILL ALLOW FOR SOME RAPID FOG DEVELOPMENT. HAVE MAINLY GONE WITH IFR AND LIFR THROUGH 13Z WITH ONLY SLOW IMPROVEMENT DURING THE DAY WITH VFR POSSIBLE AFTER 18Z BUT THIS MAY BE OPTIMISTIC AS LOW LEVEL MOISTURE LINGERS AND ISENTROPIC ASCENT MAY GET GOING AGAIN BY AROUND 21Z. && .MARINE...FRONTAL BOUNDARY BISECTS THE COASTAL WATERS WITH SLIGHTLY STRONGER WIND N OF FRONT WHERE BUOY 41008 HAD 16 KT AT 08Z. WILL HIGHLIGHT SCEC FOR THE OFFSHORE NE MARINE ZONE FOR MAINLY SEAS AS CURRENT AND PRIOR MODEL RUNS SHOW WINDS SHOULD COME DOWN A BIT DURING THE DAY. WINDS ARE EXPECTED TO INCREASE GRADUALLY ON TUE AS THE FRONT OR A COASTAL TROUGH DEVELOPS PINCHING THE PRESSURE GRADIENT...THEN A STRONG COLD FRONT SWEEPS THROUGH THU WITH RAPID INCREASES IN NW FLOW THROUGH FRIDAY. PATCHY DENSE FOG WILL LIKELY REMAIN A HAZARD FOR THE NEARSHORE WATERS THIS MORNING AND TUE MORNING AND HAVE INCLUDED IN THE CWF PACKAGE. && .PRELIMINARY POINT TEMPS/POPS... AMG 65 48 66 49 / 10 10 10 20 SSI 70 54 66 55 / 10 10 10 30 JAX 75 54 69 56 / 10 10 20 30 SGJ 75 60 70 61 / 10 20 30 40 GNV 77 55 71 56 / 10 10 20 40 OCF 79 57 75 59 / 20 20 30 30 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR ALACHUA- BRADFORD-CLAY-DUVAL-MARION-NASSAU-PUTNAM-ST JOHNS. GA...NONE. AM...NONE. && $$ PP/ARS/AW