911
FXUS62 KKEY 041858
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
258 PM EDT THU SEP 4 2025
..NEW AVIATION
AVIATION
(18Z TAFS)
ISSUED AT 254 PM EDT THU SEP 4 2025
LIGHT SHOWERS WILL CONTINUE TO MOVE SOUTHEASTERLY ACROSS BOTH EYW
AND MTH THROUGH LATE THIS EVENING. WHILE SHOWERS WILL BE CONSTANT,
LIGHTNING STRIKES WILL BE MORE RARE AS A MAJORITY IS STRATIFORM
RAIN. THERE WILL BE A BREAK IN SHOWER ACTIVITY TONIGHT AROUND 00Z
BEFORE REIGNITING IN THE MORNING HOURS. NEAR SURFACE WINDS WILL
BE SOUTHWEST TO WESTERLY AT NEAR 10 KNOTS.
PREVIOUS DISCUSSION
ISSUED AT 1044 AM EDT THU SEP 4 2025
ANOTHER YUCKY MORNING FOR THE FLORIDA KEYS. KAMX RADAR DETECTS
WIDESPREAD SHOWERS WITH SCATTERED THUNDERSTORMS THROUGHOUT THE
CWA. WHILE A MAJORITY OF THE ISLAND CHAIN SAW A LITTLE BREAK IN
SHOWERS AND KEY WEST EVEN SAW SUNSHINE FOR A FEW MINUTES, THAT
RELIEF WAS BRIEF AS RADAR SHOWS A LARGE AREA OF CONVECTION MOVING
TOWARDS LAND. THE 12Z KKEY SOUNDING THIS MORNING MEASURED 2.34
INCHES WHICH IS NOT RECORD BREAKING, BUT WELL ABOVE THE 90
PERCENTILE FOR THE DAY. WINDS ACROSS THE REEF ARE CURRENTLY
SOUTHWEST TO WEST AT 10 TO 15 KNOTS. LITTLE CHANGE IS EXPECTED
TODAY IN TERMS OF SYNOPTIC PATTERN RESULTING IN VERY SIMILAR
CONDITIONS THAT WE'VE BEEN EXPERIENCING OVER THE LAST FEW DAYS.
THEREFORE, WE WILL SEE YET ANOTHER WET DAY, WITH A POSSIBLE LULL
IN THE EVENING BEFORE FIRING OFF AGAIN. FOR WINDS, A BRIEF SURGE
OF NEAR 15 KNOTS IS POSSIBLE IN THE COASTAL WATERS BEFORE SETTLING
BACK TO 10 TO 15 KNOTS. NO CHANGES WERE NEEDED TO THIS UPDATE AS
EVERYTHING IS ON TRACK.
FORECAST
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 1044 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.
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...AP
AVIATION/NOWCASTS....AP
DATA ACQUISITION.....AP
VISIT US ON THE WEB AT WEATHER.GOV/KEY
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSKEYWEST
WWW.TWITTER.COM/NWSKEYWEST
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page