FXUS62 KKEY 201607
AFDKEY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1107 AM EST TUE JAN 20 2009
.DISCUSSION...
A DEEP LONG WAVE TROUGH OVER EASTERN NORTH AMERICA IS BEING
REINFORCED BY ADDITIONAL EQUATORWARD-MOVING SHORT WAVE ENERGY THIS
MORNING. A SURFACE CYCLONE OFFSHORE THE CAROLINAS HAS DEEPENED BELOW
1000MB AND IS ASSISTING IN THE TRANSPORT OF COLD POLAR AIR SOUTHWARD
INTO THE GULF BASIN. WINDS IN THE FLORIDA KEYS SHIFTED FROM WEST TO
NORTHWEST EARLIER THIS MORNING AS A SHEAR LINE THAT RACED OUT AHEAD
OF A PRESSURE TROUGH TRAVERSED THE KEYS. THE APPROACHING TROUGH IS
ASSOCIATED WITH THE LEADING EDGE OF AN AREA OF STRONG COLD THERMAL
ADVECTION...AND SHOULD BE PASSING THROUGH THE KEYS IN THE NEXT FEW
HOURS. AS A CONSEQUENCE...TEMPERATURES WILL BE STEADY FROM 68 TO 70F
FOR ANOTHER HOUR OR TWO BEFORE BEGINNING A SLOW FALL INTO THE MID 60S
BY LATE THIS AFTERNOON. NORTHWEST WINDS WILL SURGE THROUGH THE
AFTERNOON...PEAKING TONIGHT. THE MID-LEVEL OVERCAST WILL THIN BY LATE
THIS AFTERNOON. HOWEVER...LOW-LEVEL STRATOCUMULUS CLOUDS WILL
THICKEN...AND A FEW SPRINKLES WILL BE POSSIBLE THROUGH THIS EVENING.
FORECASTS HAVE ALREADY BEEN UPDATED FOR THE TRANSITION IN WEATHER
EXPECTED THIS AFTERNOON.
&& 
.MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL ZONES. A SHEAR LINE AND
ASSOCIATED LINE OF LIGHT SHOWERS MOVED THROUGH ALL OF THE KEYS THIS
MORNING. WINDS TURNED NORTHWEST IN WAKE OF THIS BOUNDARY. NORTHWEST
BREEZES WILL INCREASE TO NEAR 25KT...WITH GUSTS NEAR 30KT...BY
SUNSET AS A TROUGH ASSOCIATED WITH A DEEPENING GALE CENTER OFFSHORE
THE CAROLINAS MOVES THROUGH THE KEYS. SEAS WILL BUILD IN A NORTHWEST
SWELL...WITH SIGNIFICANT WAVE HEIGHTS EXCEEDING 10FT IN GULF OF
MEXICO WATERS BEYOND 40 NM WEST OF MAINLAND MONROE AND IN THE
VICINITY OF THE DRY TORTUGAS...AS WELL AS AREAS WEST AND SOUTH OF THE
TORTUGAS. ISOLATED SHOWERS WILL END THIS AFTERNOON BEYOND THE REEF...
BUT SPRINKLES ARE POSSIBLE ALL ZONES THROUGH THIS EVENING.
&&
.AVIATION...
FOR THE BALANCE OF TODAY...VFR CEILINGS OF AROUND 3500 FEET WILL 
PREDOMINATE AT THE KEYS ISLAND TERMINALS...BUT SPELLS OF MVFR 
CEILINGS ARE POSSIBLE THIS AFTERNOON. NORTHWEST WINDS /330 DEGREES/
OF 10 TO 15 KNOTS WILL INCREASE TO NEAR 20 KNOTS EARLY THIS
AFTERNOON...WITH FREQUENT GUSTS OF AROUND 30 KNOTS.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...SMALL CRAFT ADVISORY FOR GMZ031-GMZ032-
     GMZ033-GMZ052-GMZ053-GMZ054-GMZ072-GMZ073-GMZ074-GMZ075.
&&
$$
PUBLIC/MARINE.........KASPER
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......WAH
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