Area Forecast Discussion
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FXUS62 KKEY 231850
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
250 PM EDT SAT AUG 23 2014

.DISCUSSION...DEEP ANTICYCLONIC FLOW RESIDES ACROSS THE SOUTHERN
MISSISSIPPI VALLEY. JUST TO OUR SOUTHEAST...A PINCHED TUTT- LIKE CELL
CONTINUES TO PRESS WEST ACROSS THE FLORIDA STRAITS AND CENTRAL CUBA.
THE WESTERN ATLANTIC RIDGE HAS BEEN ASSAULTED BY A TROPICAL
DISTURBANCE NORTHWEST OF HISPANIOLA AND ENERGY FROM THE MID
LATITUDES WHICH HAS CARVED OUT LOWER HEIGHTS ACROSS THE NORTHWEST
ATLANTIC. DUE TO THE CYCLONIC CURVATURE TO OUR SOUTHEAST AND THE
SURFACE RIDGING ACROSS THE NORTH-CENTRAL GULF OF MEXICO...GENTLE
NORTH TO NORTHEASTERLY BREEZES PREVAIL ACROSS THE FLORIDA KEYS AND
AREA COASTAL WATERS. A NARROW RIBBON OF DRY AIR LIES ACROSS SOUTH-
SOUTHWEST FLORIDA AND THE FLORIDA KEYS...WELL DEPICTED BY MIMIC TPW
AND VISIBLE SATELLITE LOOPS. THIS MORNING`S RAOB OBSERVATION AND
RECENT SATELLITE BASED SOUNDINGS SAMPLED THIS DRY AIR AT OR ABOVE
850 MB. ISOLATED SHOWERS AND A FEW THUNDERSTORMS HAVE PERSISTED
ACROSS THE SOUTHEASTERN GULF WATERS NORTHWEST OF THE TORTUGAS AND
ALSO ACROSS THE SOUTHEASTERN HALF OF THE FLORIDA STRAITS.

.SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...THE TROPICAL DISTURBANCE
NORTHWEST OF HISPANIOLA WILL PUSH TO THE NORTHWEST...REINFORCING THE
NORTHEASTERLY STEERING FLOW ACROSS SOUTHERN FLORIDA AND THE FLORIDA
KEYS. IF MAINLAND CONVECTION IS ABLE TO FIRE...UNSUPPRESSED BY THE
DISTURBANCE`S EFFLUENT...THEN WE WILL BE RIGHT DOWN THE BARREL ON SUNDAY
AND MONDAY AFTERNOONS. HOWEVER...GIVEN THE UNCERTAINTY WITH THE
FUTURE DEVELOPMENT AND TRACK OF THE TROPICAL DISTURBANCE...WE MAKE NO
REAL DISTINCTION IN RAIN CHANCES THROUGH THE SHORT TERM. THE BEST
CHANCES SEEM TO BE MONDAY AND MONDAY NIGHT...AS THE OUTER FRINGES OF
THE CYCLONIC ENVELOPE AID CONVECTIVE ELEMENTS ACROSS MAINLAND
FLORIDA.

&&

.LONG TERM (TUESDAY THROUGH SATURDAY)...HIGHER THAN NORMAL
UNCERTAINTY CONCERNING THE FUTURE EVOLUTION OF 96L. STEERING FLOW
REMAINS NORTHERLY OR NORTHEASTERLY...KEEPING THE KEYS WITHIN THE
ALLEY OF MAINLAND CONVECTIVE OUTFLOWS. THE WIND GRIDS PORTRAY LOW
PRESSURE SLOWLY PUSHING THROUGH THE BAHAMAS...PARALLELING THE FLORIDA
COAST...THEN LIFTING NORTHEAST UP THE ATLANTIC SEA BOARD. THIS
SOLUTION APPEARS AS GOOD AS ANY AT THE CURRENT TIME.

&&

.MARINE...AN ATLANTIC RIDGE OF HIGH PRESSURE ACROSS SOUTH CENTRAL
FLORIDA WILL RETREAT EASTWARD TONIGHT THROUGH MONDAY. LOW PRESSURE
CURRENTLY IN THE VICINITY OF HISPANIOLA IS EXPECTED TO STRENGTHEN
WHILE LIFTING NORTHWESTWARD ACROSS THE BAHAMAS THROUGH THE MIDDLE OF
THE WEEK.

&&

.AVIATION...DUE TO CELLS MIGRATING SOUTH SOUTHWESTWARD OFF THE SOUTH
FLORIDA MAINLAND...THE BEST CHANCE OF A VICINITY SHOWER/THUNDERSTORM
OR SUB VFR EPISODE AT THE KEY WEST AND MARATHON TERMINALS WILL BE
LATE THIS AFTERNOON AND EVENING. OTHERWISE...VFR CONDITIONS WILL
OCCUR. NORTH TO NORTHEAST WINDS OF LESS THAN 10 KNOTS CAN BE
ANTICIPATED.

&&

.PRELIMINARY POINT TEMPS/POPS...

KEY WEST 92 83 92 82 / 20 20 20 30
MARATHON 93 82 93 81 / 20 20 20 20

&&

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

$$

PUBLIC/MARINE.........CLR
AVIATION/NOWCASTS.....APA
DATA COLLECTION.......VICKERY

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