Area Forecast Discussion
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000
FXUS62 KKEY 310933
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
533 AM EDT THU JUL 31 2014

.DISCUSSION...
.CURRENTLY...
LATE EVENING AND EARLY OVERNIGHT SHOWER AND THUNDERSTORM ACTIVITY WAS
RELATIVELY POTENT TONIGHT COMPARED TO RECENT ACTIVITY...BUT MOST
SHOWERS AND THUNDERSTORMS HAVE DRAWN TO A CLOSE ACROSS THE SERVICE
AREA AT THIS TIME. SKIES ARE PARTLY TO MOSTLY CLOUDY MOSTLY DUE TO A
LINGERING DENSE CIRRUS SHIELD THAT IS DRAPED ACROSS THE ISLAND CHAIN
AT THIS TIME. WINDS ARE LIGHT AND VARIABLE AT ALL ISLAND AND MARINE
BASED OBSERVING SYSTEMS ACROSS THE KEYS. EVENING SOUNDING CAME IN
WITH MOIST AND UNSTABLE CONDITIONS UP TO 700 MB...WITH A MODEST DRY
PATCH AND ASSOCIATED ISOTHERMAL LAYER AT THAT LEVEL. RELIABLE MODEL
SOUNDINGS SHOW VERY FEW CHANGES ARE INDICATED IN THAT OBSERVATION AT
THIS HOUR. A LOW TO MIDLEVEL TROUGH IS CURRENTLY LOSING ITS IDENTITY
ACROSS SOUTH FLORIDA AND THE KEYS...LEAVING A VERY DIFFUSE PRESSURE
PATTERN ACROSS THE ISLANDS WITH BUT LINGERING DEEP MOISTURE REMAINS
AROUND 2.0 TO 2.2 INCHES ACROSS THE CWA.

.TODAY...
EXPECT THAT THE VIGOROUS NATURE OF EARLY NOCTURNAL CONVECTION
SHOULD HAVE TEMPORARILY STABILIZED THE THERMODYNAMIC ENVIRONMENT
ACROSS THE KEYS...AND NEARSHORE WATERS. EXPECT THAT THIS IN TURN WILL
LIMIT SHOWER AND THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE
DAY. BY NOON HOWEVER...EXPECT DAYTIME HEATING OF ISLANDS WILL COMBINE
WITH EXCESSIVELY WARM NEARSHORE WATER TEMPERATURES AND CONTINUED LIGHT
WINDS ACROSS THE KEYS TO INSPIRE PLENTIFUL CLOUD LINE
BOUNDARIES...SHOWERS...AND THUNDERSTORMS. THE ONLY LIMITING FACTOR
FOR THIS OUTCOME THAT ADDS UNCERTAINTY WILL BE THE SEA BREEZE
CIRCULATIONS OVER THE MAINLANDS OF FLORIDA AND CUBA. EXPECT THESE
TELE-CONNECTIONS TO BE MINOR INITIALLY...AND THEREFORE FEEL THAT NOON
TO 2 PM LOCAL TIME WILL BE THE PRIMARY TIMES OF PREVALENT SHOWER AND
THUNDERSTORM ACTIVITY...AT COVERAGE AMOUNTS IN THE HIGH END OF THE
SCATTERED CATEGORY (AROUND 50 PERCENT). OTHERWISE...TEMPS WILL REMAIN
ON THE HIGH SIDE OF CLIMO VALUES TODAY...AND OVERNIGHT LOWS SHOULD
REMAIN WARM AS WELL EXCEPT IN RAIN COOLED ENVIRONMENTS.

.LONG TERM...
VERY FEW CHANGES WILL BE REQUIRED IN THE MEDIUM AND LONG TERM
PORTIONS OF THE FORECAST. A RIDGE WILL REMAIN MIRED ACROSS THE KEYS
THROUGH AT LEAST FRIDAY...AND HIGH ATMOSPHERIC MOISTURE CONTENT WILL
KEEP THE RAIN CHANCES ON THE HIGH SIDE OF CLIMATOLOGY. THE REMNANTS
OF A LARGE TROPICAL WAVE WITH DUBIOUS IDENTITY WILL CROSS THE KEYS
FROM SATURDAY THROUGH EARLY MONDAY...BRINGING INCREASED RAIN CHANCES
TO THE KEYS THROUGH THAT PERIOD. WINDS SHOULD REMAIN GENERALLY LIGHT
THOUGH THEY WILL TAKE ON A MORE CLIMATOLOGICAL TRADE WIND IDENTITY
AHEAD OF...AND ALONG THIS TROPICAL WAVE.

&&

.MARINE...
LIGHT AND VARIABLE WINDS AND GENERALLY BENIGN SEAS WILL PREVAIL
THROUGH THE NEXT COUPLE OF DAYS...THOUGH MARINERS SHOULD STILL BE
PREPARED FOR THE EVENT OF GUSTY WINDS IN AND AROUND SHOWERS AND
THUNDERSTORMS...WITH SHORT-DURATION HIGHER SEAS POSSIBLE IN THE NEAR
STORM ENVIRONMENT AS WELL. OTHERWISE...A GENERALLY EAST-SOUTHEAST
LIGHT FLOW SHOULD SET UP BY LATE FRIDAY ACROSS THE KEYS.


&&

.AVIATION...
VFR CONDITIONS WILL PREVAIL AT EYW AND MTH THIS MORNING. MVFR OR
LOWER CONDITIONS ARE CONCEIVABLE AT EYW AND MTH THIS AFTERNOON AND
THIS EVENING AS ISLAND CUMULUS CLOUD LINES BUILD NEAR OR DIRECTLY
OVER THE FLORIDA KEYS. THIS POSSIBILITY IS NOT GREAT ENOUGH TO PLACE
IN THE TERMINAL FORECASTS AT THIS TIME. SUSTAINED WEST TO NORTHWEST
WINDS NEAR 10 KNOTS FROM JUST OFF THE SURFACE TO ABOUT 8000 FEET
WILL BECOME LIGHT AND VARIABLE THIS AFTERNOON.

&&

.CLIMATE...
ON THIS DATE IN KEYS WEATHER HISTORY...IN 1874...THE HIGH
TEMPERATURE IN KEY WEST WAS 95 DEGREES. THIS SET THE DAILY RECORD
FOR MAXIMUM TEMPERATURE MEASURED IN KEY WEST ON JULY 31ST...A RECORD
WHICH STILL STANDS 140 YEARS LATER. TEMPERATURE RECORDS AT KEY WEST
DATE BACK TO 1872.

&&

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

$$

PUBLIC/MARINE.........MSB
AVIATION/NOWCASTS.....BS

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