873
FXUS62 KKEY 050801
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
401 AM EDT FRI SEP 5 2025
..NEW DISCUSSION, MARINE, AVIATION
DISCUSSION
ISSUED AT 400 AM EDT FRI SEP 5 2025
A VERY EARLY SEASON MID LATITUDE TROUGH REMAINS ENTRENCHED ACROSS
EASTERN NORTH AMERICA. THIS HAS MAINTAINED A MOISTURE RICH SURFACE
THROUGH LOWER LEVEL TROUGH WHICH STRADDLES SOUTH AND CENTRAL
FLORIDA. THIS SETUP AT ANY TIME OF YEAR IS USUALLY QUITE WET.
AFTER A MOSTLY QUIET EVENING, SHOWERS AND A THUNDERSTORM OR TWO
HAVE BEGUN TO FILL IN. THUS FAR, A MORE BACKED STEERING FLOW HAS
MEANT MOST OF THIS ACTIVITY HAS GLIDED NORTHEASTWARD ACROSS OUR
WESTERN AND NORTHWESTERN WATERS WITH ONLY ISOLATED SHOWERS
AFFECTING THE ARCHIPELAGO.
THE VERY WET ENVIRONMENT AND TROUGHING WILL REMAIN STATIONARY
TODAY INTO TOMORROW. WINDS WILL REMAIN LIGHT TO GENTLE AND MOSTLY
SOUTHWESTERLY. MEANWHILE, A SOUTHERN STREAM SHORTWAVE TROUGH IS
EXPECTED TO SHARPEN LATER THIS AFTERNOON, POTENTIALLY ADDING SOME
UPPER LEVEL SUPPORT TO AN ALREADY PRIMED SETUP. EXPECT VERY HIGH
RAIN CHANCES TODAY INTO TONIGHT. TEMPERATURES WILL BE HIGHLY
DEPENDENT ON THE DISTRIBUTION AND PERSISTENCE OF CONVECTION AND
CLOUD COVER. HIGHS SHOULD BROADLY BE IN THE UPPER 80S WITH DEW
POINTS IN THE MID 70S.
THE PREVIOUSLY MENTIONED SHORTWAVE TROUGH WILL LIFT OUT LEAVING A
FRACTURED RIDGE ACROSS OUR AREA THIS WEEKEND. ALSO, A SURFACE
THROUGH LOWER LEVEL ATLANTIC RIDGE WILL SWING NORTHWARD OUT OF
CUBA INTO THE KEYS AND SOUTH FLORIDA. THIS WILL LEAVE WEAK
TROUGHING NOT TO FAR OFF TO OUR NORTH AND THE BROAD SWATH OF
MOISTURE STAGNANT ACROSS OUR AREA. ALL THIS POINTS TO RAIN
CHANCES REMAINING ABOVE NORMAL. HOWEVER, CUBAN SHADOW EFFECTS MAY
PROVIDE PERIODIC BREAKS.
THROUGH THE FIRST HALF OF NEXT WEEK THE MID LATITUDE TROUGH IS
EXPECTED TO LIFT OUT. HOWEVER, THE OBNOXIOUS LOWER LEVEL TROUGH
AND ASSOCIATED MOISTURE WILL LINGER ACROSS FLORIDA AND ADJACENT
WATERS AND WILL PROBABLY GET AN ASSIST BY AN AMPLIFYING SOUTHERN
STREAM UPPER TROUGH OVER THE GULF. HENCE, CONTINUED ABOVE NORMAL
RAIN CHANCES. FOR NOW, HAVE MAINTAINED HIGH CHANCE POPS THROUGH
THE EXTENDED, WHICH IS MOSTLY IN LINE WITH GUIDANCE.
MARINE
ISSUED AT 400 AM EDT FRI SEP 5 2025
A STUBBORN TROUGH WILL REMAIN DRAPED ACROSS SOUTH AND CENTRAL
FLORIDA OVER THE NEXT COUPLE OF DAYS. THIS WILL KEEP WINDS LIGHT
TO GENTLE OUT OF THE SOUTH TO SOUTHWEST. WITH THAT SAID, THERE IS
THE POTENTIAL FOR A MODERATE SOUTHERLY WIND SURGE ON WATERS NEAR
NORTH KEY LARGO THIS AFTERNOON AND EARLY EVENING. CONVECTIVE
CHANCES WILL REMAIN QUITE HIGH. AN ATLANTIC RIDGE WILL SWING
NORTHWARD INTO THE KEYS THIS WEEKEND AND NUDGE THE PERSISTENT
TROUGH NORTHWARD. THIS WILL SHIFT SLACKENING BREEZES MORE
SOUTHERLY. CONVECTIVE COVERAGE SHOULD TREND DOWNWARDS, BUT REMAIN
ABOVE SEASONAL NORMS. THIS IS DUE TO LINGERING INFLUENCES OF MID
LATITUDE TROUGHING ALOFT AND LOWER LEVEL MOISTURE REMAINING VERY
HIGH.
AVIATION
(06Z TAFS)
ISSUED AT 400 AM EDT FRI SEP 5 2025
WHILE VFR CONDITIONS WILL LARGELY PREVAIL AT THE TERMINALS THIS
MORNING, EPISODES OF PASSING SHOWERS AND THUNDERSTORMS ARE LIKELY TO
PRODUCE BRIEF DIPS INTO SUB-VFR CIGS AND VISIBILITIES AT TIMES.
RADAR AND MODEL TRENDS SUPPORT INCLUSION OF VCSH THROUGHOUT THE TAF
PERIOD, BUT SPECIFIC TIMING UNCERTAINTY AND THE TRANSIENT NATURE OF
CATEGORICAL CHANGES NECESSITATE LEAVING MORE SPECIFIC MENTIONS TO
FUTURE TAFS AND AMENDMENTS. OUTSIDE OF SHOWER AND THUNDERSTORM
ACTIVITY, WINDS WILL REMAIN GENERALLY FROM THE SOUTHWEST AT NEAR 10
KNOTS.
CLIMATE
ON THIS DAY IN KEYS WEATHER HISTORY IN 1900, A TROPICAL STORM MOVED
NORTHWEST OFF OF CUBA, PASSING ABOUT 40 MILES SOUTHWEST OF KEY WEST.
A MINIMUM PRESSURE OF 29.44" (977 MB) WAS RECORDED, ALONG WITH A
PEAK SUSTAINED WIND OF 40 MPH. THE STORM SUBSEQUENTLY INTENSIFIED
IN THE GULF AND WENT ON TO FAMOUSLY DEVASTATE GALVESTON, TEXAS.
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...11
AVIATION/NOWCASTS....MC
DATA ACQUISITION.....MC
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