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000
FXUS62 KKEY 200908
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
508 AM EDT WED AUG 20 2014

.DISCUSSION...LIGHT EAST TO SOUTHEAST BREEZES PREVAIL ACROSS THE
FLORIDA KEYS AND AREA COASTAL WATERS. AFTER A RELATIVELY QUIET
EVENING...ISOLATED THUNDERSTORMS HAVE DRIFTED WEST ACROSS THE
SOUTHEASTERN GULF WATERS OVERNIGHT. THE MOST RECENT SCANS OF RADAR
REVEAL ISOLATED SHOWERS PUSHING INTO THE SOUTHEASTERN FLORIDA
STRAITS. ACCORDING TO MIMIC TPW IMAGERY...A RIBBON OF ENHANCED
MOISTURE EXTENDS FROM WEST TO EAST...FROM THE SOUTH-CENTRAL GULF OF
MEXICO TO THE NORTHERN BAHAMAS. THE MID TO UPPER LEVEL HEIGHT CHANGES
FROM THE 00Z RAOBS INDICATE RISING HEIGHTS ACROSS MUCH OF THE
MISSISSIPPI RIVER VALLEY. AS A RESULT...THE WESTERN ATLANTIC RIDGE
AXIS HAS SPLIT INTO TWO PIECES...ONE NOW FAVORED ACROSS THE CENTRAL
AND NORTHERN GULF...AND THE OTHER EXTENDING EAST FROM EASTERN
FLORIDA.

.SHORT TERM (TODAY THROUGH FRIDAY)...A DEEP ANTICYCLONIC CIRCULATION
WILL DEVELOP IN THE NORTHERN GULF TODAY AND TONIGHT...THEN VACILLATE
AND BROADEN ALONG THE COASTAL GULF STATES THURSDAY THROUGH FRIDAY.
MOISTURE APPEARS PLENTIFUL THROUGH THE SHORT TERM...AND STEERING
FLOW WILL SWING FROM NORTHEASTERLY TODAY...TO MAINLY EAST THEREAFTER.
THUS...A CLOUD LINE THIS AFTERNOON MAY BE ENHANCED BY MAINLAND
OUTFLOWS THIS EVENING. EXPECT THE MARITIME EASTERLIES TO SPREAD
ACROSS THE KEYS FROM EAST TO WEST TONIGHT...LEADING TO CONFLUENT FLOW
AND ENHANCED RAIN CHANCES. RAIN CHANCES WILL BE NEAR NORMAL THURSDAY
NIGHT THROUGH FRIDAY...AS A NOCTURNAL REGIME OF LATE NIGHT AND EARLY
MORNING SHOWERS DEVELOP WITHIN UNDULATIONS OF THE MEAN FLOW.
TEMPERATURES WILL CLIMB INTO THE LOWER 90S EACH AFTERNOON...AND
OVERNIGHT LOWS WILL REMAIN SULTRY...ASIDE FROM ANY RAIN COOLED AREAS.

&&

.LONG TERM (FRIDAY NIGHT THROUGH TUESDAY)...SIMILAR TO THE END OF THE
SHORT TERM...A BARBELL SHAPED COMPLEX OF MID-UPPER LEVEL
ANTICYCLONIC FLOW WILL REMAIN ACROSS THE AL-MS TWIN STATES AND THE
WESTERN ATLANTIC. THE NOCTURNAL REGIME WILL PREVAIL. THEREAFTER...THE
UNCERTAIN FUTURE EVOLUTION OF 96L WILL DETERMINE THE FORECAST. THE
CURRENT CONSENSUS...WHICH IS BOUND TO CHANGE...BRINGS AT LEAST A
TROPICAL WAVE THROUGH THE CARIBBEAN...SOUTH OF CUBA...THEN THROUGH
THE YUCATAN AND INTO THE GULF OF MEXICO. EXPECT A TIGHTENED PRESSURE
GRADIENT AS THIS SYSTEM PASSES TO OUR SOUTH...RESULTING IN
FRESHENING...MAINLY EAST BREEZES. THE DESCRIBED SCENARIO WOULD RESULT
IN A PERIOD OF FAST MOVING SHOWERS AT THE END OF THE LONG TERM.

&&

.MARINE...HIGH PRESSURE WILL REMAIN ACROSS THE WESTERN ATLANTIC AND
THE NORTHERN GULF OF MEXICO THROUGH SUNDAY. EXPECT MAINLY MODERATE
EASTERLY BREEZES AND A PRECIPITATION REGIME WHICH FAVORS THE LATE
NIGHT AND EARLY MORNING HOURS.

&&

.AVIATION....AVIATION...VFR CONDITIONS WILL PREVAIL AT BOTH THE KEY
WEST AND MARATHON TERMINALS THROUGH WEDNESDAY MORNING AND AFTERNOON.
MVFR CONDITIONS ARE POSSIBLE IN LATE MORNING AND AFTERNOON
SHOWERS...BUT THE PROBABILITY IS TOO LOW TO INCLUDE IN THE TERMINAL
FORECAST. THEREFORE...AMENDMENTS WILL BE MADE IF NECESSARY. SURFACE
WINDS AT BOTH TERMINALS WILL BE MAINLY FROM THE EAST NEAR 5 KNOTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  92  82  91  84 / 40 40 30 30
MARATHON  93  81  93  83 / 40 40 30 30

&&

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

$$

PUBLIC/MARINE.........CLR
AVIATION/NOWCASTS.....DEVANAS
DATA COLLECTION.......FLING

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