000
FXUS62 KKEY 250217
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
920 PM EST TUE NOV 24 2009

.DISCUSSION...
.CURRENTLY...
KBYX DETECTS SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS OVER THE 
MIDDLE AND LOWER KEYS...AS WELL AS OVER THE NEARSHORE AND OFFSHORE 
WATERS WEST AND SOUTH OF THE MIDDLE AND LOWER KEYS. ELSEWHERE...KBYX 
DETECTS NO PRECIPITATION ECHOES IN THE REMAINDER OF THE FORECAST 
AREA. SKIES OVER THE ISLAND CHAIN ARE VARIABLY CLOUDY. WINDS OVER 
LAND ARE EAST AT 10 TO 15 MPH. C-MAN WINDS...ON AVERAGE...ARE EAST 
TO SOUTHEAST NEAR 15 KNOTS...WITH GUSTS NEAR 20 KNOTS. TEMPERATURES 
ARE NEAR 80 DEGREES. ONLY ABOUT FOUR DEGREES OF COOLING IS EXPECTED 
OVERNIGHT DUE TO GENTLE EAST TO SOUTHEAST SURFACE WINDS OVER WATER 
WITH TEMPERATURES NEAR 80 DEGREES.

.SHORT TERM (OVERNIGHT)...
A FRONTAL BOUNDARY WILL REMAIN STATIONARY ACROSS SOUTH CENTRAL 
FLORIDA...JUST NORTH OF LAKE OKEECHOBEE OVERNIGHT. FARTHER WEST...
BROAD CYCLONIC FLOW IN THE EAST AND CENTRAL GULF OF MEXICO WILL 
AMPLIFY TONIGHT. THE 00Z KKEY SOUNDING IS MODERATELY UNSTABLE AND 
MOIST...WITH A PRECIPITABLE WATER (PWAT) VALUE JUST UNDER ONE AND 
THREE QUARTERS OF AN INCH. ATMOSPHERIC MOISTURE SHOULD INCREASE 
OVERNIGHT. BY SUNRISE WEDNESDAY...PWAT VALUES SHOULD BE JUST ABOVE 
ONE AND THREE QUARTERS OF AN INCH. CYCLONIC FLOW IN ALL LEVELS OF 
THE ATMOSPHERE COUPLED WITH PLENTY OF MOISTURE AND INSTABILITY IN 
PLACE WARRANTS POPS TONIGHT WHICH ARE WELL ABOVE NORMAL FOR THIS 
TIME OF YEAR. THE ZONE FORECASTS FOR THE FLORIDA KEYS HAS ALREADY 
BEEN UPDATED. NO ADDITIONAL UPDATES ARE EXPECTED. 

&&

.MARINE...
SMALL CRAFT ARE URGED TO EXERCISE CAUTION ON ATLANTIC WATERS 
OVERNIGHT AND WEDNESDAY MORNING DUE TO SUSTAINED SURFACE WINDS OF 15 
TO 20 KNOTS. NO ADVISORIES OR CAUTIONARY STATEMENTS EXPECTED 
WEDNESDAY AFTERNOON THROUGH AT LEAST THURSDAY MORNING. A COLD FRONT 
WILL LIKELY CROSS THE FLORIDA KEYS THURSDAY AFTERNOON OR THURSDAY 
EVENING. A SMALL CRAFT ADVISORY MAY BE REQUIRED FOR ALL KEYS WATERS 
THURSDAY NIGHT AND FRIDAY. SUSTAINED NORTH TO NORTHEAST SURFACE 
WINDS OF 15 TO 20 KNOTS ARE POSSIBLE ON ALL KEYS WATERS FRIDAY 
NIGHT. NO ADVISORIES OR CAUTIONARY STATEMENTS EXPECTED SATURDAY AND 
SUNDAY. 

&&

.AVIATION...
ALTHOUGH VFR CONDITIONS SHOULD PREVAIL TONIGHT AND WEDNESDAY 
MORNING...THERE WILL BE BRIEF PERIODS OF MVFR CIGS AND VIS IN 
SHOWERS. THESE ARE NOT IN THE TAFS DUE TO SHORT DURATION AND RANDOM 
TIMING OF THE PERIODS. BY 10Z WEDNESDAY...EXPECT MVFR CIGS AND VIS 
TO BECOME MORE COMMON. CURRENTLY HANDLING THIS WITH A VCSH...BUT 
WILL TRY TO PROVIDE SOME MORE PRECISE INFO VIA TEMPOS IN THE NEXT 
TAF ISSUANCES. WINDS WILL COME AROUND TO THE SOUTHEAST AFTER 
SUNRISE...AND SHIFT TO THE SOUTHWEST DURING WEDNESDAY AFTERNOON. IT 
IS POSSIBLE TO SEE 10-15 KNOTS OF SOUTHERLY CROSSWIND BRIEFLY DURING 
THE EARLY AFTERNOON HOURS WEDNESDAY. 

&&

.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...IN 1925...THE HIGH 
TEMPERATURE IN KEY WEST WAS ONLY 66 DEGREES. THIS SET THE DAILY 
RECORD FOR COOLEST HIGH TEMPERATURE MEASURED IN KEY WEST ON NOVEMBER 
24TH...A RECORD WHICH STILL STANDS 84 YEARS LATER. 

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.

&&

$$

PUBLIC/MARINE/FIRE/CLIMATE/DIGITAL...BS
AVIATION/NOWCASTS....................STRAHAN

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