274
FXUS62 KKEY 040823
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
423 AM EDT THU SEP 4 2025
..NEW DISCUSSION, MARINE, AVIATION
DISCUSSION
ISSUED AT 423 AM EDT THU SEP 4 2025
CONVECTION IS GETTING AN EARLY START AROUND THE FLORIDA KEYS THIS
MORNING. AFTER YESTERDAY'S ROUNDS OF WIDESPREAD SHOWERS AND
SCATTERED THUNDERSTORMS, A LULL SETTLED AROUND THE ISLAND CHAIN
FOR A FEW HOURS. THIS QUIET DID NOT LAST LONG HOWEVER, AS A LINE
OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS RECENTLY DEVELOPED
ACROSS THE MIDDLE KEYS AND EXTENDED UP TOWARDS THE WEST COAST OF
SOUTH FLORIDA. THIS ACTIVITY HAS SINCE DRIFTED INTO THE EASTERN
STRAITS WITH KAMX RADAR DETECTING A FEW MORE PULSING SHOWERS
SPAWNING OVER THE DEEP GULF WATERS AND THE LOWER AND MIDDLE KEYS.
MODERATE SOUTHWEST BREEZES ARE OBSERVED ALONG THE REEF STATIONS
WEST OF ONGOING CONVECTION WITH LIGHT TO GENTLE BREEZES STILL
EXPERIENCED NEAR THE UPPER KEYS. TEMPERATURES ARE THE ONLY VALUES
SIMILAR TO YESTERDAY AROUND THIS TIME AND ARE REPORTING IN THE
LOWER 80S ACROSS THE KEYS.
LITTLE CHANGE WITH OUR SYNOPTIC PLAYERS WILL RESULT IN ANOTHER
WET FORECAST FOR THE FLORIDA KEYS IN THE SHORT TERM. A STATIONARY
FRONT IS STILL PARKED OVER SOUTH FLORIDA AND THE KEYS WITH ITS
ASSOCIATED SURFACE TROUGH STRETCHED FROM THE GULF OUT NORTH OF THE
BAHAMAS AND WEST OF BERMUDA. THIS TROUGH CONTINUES TO PROMOTE
GENTLE TO MODERATE WESTERLY BREEZES ACROSS OUR WATERS WHILE THE
STALLED FRONT ACTS AS A LOCAL LIFTING MECHANISM FOR DEVELOPING
CONVECTION. MEANWHILE, DEEP LAYER TROUGHING REMAINS OVER EASTERN
CONUS AND LOOKS LIKE ITS HERE TO STAY FOR AT LEAST THE NEXT FEW
DAYS. YESTERDAY EVENING'S KKEY 00Z SOUNDING SHOWS A VERY MOIST
TROPICAL PROFILE WITH A ROUGHLY UNIDIRECTIONAL VERTICAL WIND
PROFILE FROM THE WEST. UPSTREAM OF OUR AREA, CIMSS MIMIC PW NOTES
A PLETHORA OF MOIST AIR PRIMED TO CONTINUE ADVECTING OVER THE
KEYS.
THUS WE ONCE AGAIN FIND OURSELVES WITH PLENTY OF MOISTURE, LIFT,
AND EVENTUALLY INSTABILITY AS THE ATMOSPHERE RECOVERS AND DAYTIME
HEAT IS REINTRODUCED INTO THE ENVIRONMENT. OPTED TO RETURN TO 80%
POPS WITH CHANCE THUNDER DURING THE DAY AS A RESULT, BUT WILL ALSO
AIM FOR 60% TONIGHT AS CONVECTION OVER THE LAST FEW DAYS HAS HAD
SOMEWHAT OF A DIURNAL SIGNAL WITH ITS LULLS. THE WEATHER
PREDICTION CENTER HAS ONCE AGAIN GIVEN THE FLORIDA KEYS A MARGINAL
RISK (LEVEL 1 OF 4) FOR EXCESSIVE RAINFALL TODAY. ANY
THUNDERSTORMS THAT TRACK OVER THE KEYS WILL BE CAPABLE OF
PRODUCING HEAVY RAINFALL.
IT STILL LOOKS LIKE WE'LL BREAK FREE OF THIS PATTERN STARTING
SATURDAY AS THE MID TO UPPER LEVEL TROUGHING AND THE SURFACE LOW
EXIT TO THE NORTHEAST. THIS WILL ALLOW WEAK RIDGING TO SLIDE BACK
INTO THE AREA WITH WINDS GRADUALLY FLIPPING BACK AROUND TO A
CLOSER TO NORMAL SOUTHEASTERLY WIND DIRECTION. WHILE THE BIG
PLAYERS FOR HEAVY RAINFALL WILL BE OUT OF THE PICTURE, ANOTHER
UNDULATION OF MOISTURE LOOKS TO SETTLE IN FROM THE EAST KEEPING
RAIN CHANCES JUST ABOVE NORMAL INTO NEXT WEEK.
MARINE
ISSUED AT 423 AM EDT THU SEP 4 2025
NO WATCHES, WARNINGS, OR ADVISORIES ARE CURRENTLY IN EFFECT FOR
THE COASTAL WATERS OF THE FLORIDA KEYS. FROM SYNOPSIS, A BROAD
SURFACE LOW ALONG A STATIONARY FRONT STRETCHING FROM THE GULF
EASTWARD TO THE FLORIDA PENINSULA WILL MAINTAIN WESTERLY WINDS
ACROSS THE FLORIDA KEYS MARINE ZONES TODAY. THE FRONT WILL REMAIN
ROOTED IN PLACE THROUGH THE NEXT FEW DAYS, WHILE THE LOW MEANDERS
NORTHEAST INTO THE WESTERN NORTH ATLANTIC, PROMOTING SOUTHWEST TO
WEST BREEZES THROUGHOUT THE WEEK. ABUNDANT MOISTURE WILL PROMOTE
WELL ABOVE NORMAL RAIN AND THUNDER CHANCES THROUGH THE END OF THE
WORK WEEK. HIGH PRESSURE SLOWLY BUILDING ACROSS THE NORTH ATLANTIC
OVER THE WEEKEND WILL SUPPORT REDUCED RAIN AND THUNDER CHANCES,
ALTHOUGH REMAINING AT OR ABOVE NORMAL.
AVIATION
(00Z TAFS)
ISSUED AT 423 AM EDT THU SEP 4 2025
THE LONG RUNNING WET WEATHER PATTERN WILL CONTINUE FOR YET
ANOTHER DAY ACROSS THE KEYS. AS A RESULT, PERIODIC ROUNDS OF SUB
VFR CONDITIONS AND GUSTY WINDS ARE EXPECTED WITH A CHANCE FOR
THUNDERSTORMS. ASIDE FROM CONVECTIVE DISTURBANCES, SURFACE WINDS
WILL GENERALLY BE GENTLE OUT OF THE WEST.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 90 79 91 80 / 80 60 80 50
MARATHON 89 79 89 80 / 80 60 80 50
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...JAM
AVIATION/NOWCASTS....11
DATA ACQUISITION.....JAM
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