563
FXUS62 KKEY 101952
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
352 PM EDT MON MAR 10 2025
..NEW DISCUSSION, MARINE, AVIATION
DISCUSSION
ISSUED AT 350 PM EDT MON MAR 10 2025
A COLD FRONT IS QUICKLY APPROACHING THE FLORIDA KEYS THIS
AFTERNOON. WHAT WAS A THIN BUT ROBUST PREFRONTAL LINE OF SHOWERS
AND SEVERAL THUNDERSTORMS HAS WEAKENED INTO A BROKEN LINE OF
MAINLY STRATIFORM SHOWERS WITH A FEW RUMBLES OF THUNDER TOSSED
AROUND WITHIN. SKIES HAVE CERTAINLY CHANGED AHEAD OF THIS LINE AS
HIGH CLOUD DEBRIS IS OBSERVED ON VISIBLE GOES 16 SATELLITE IMAGERY
COVERING OUR NORTHERN WATERS AND THE ENTIRE ISLAND CHAIN.
AS A RESULT, TEMPERATURES REMAIN LOCKED NEAR 80 ACROSS MOST LAND
AREAS. MODERATE TO FRESH SOUTHWEST TO WEST BREEZES PREVAIL ACROSS
THE REEF TRACT FOR NOW, BUT ARE PRACTICALLY VEERING AS THIS
DISCUSSION IS BEING WRITTEN WITH FRESHENING NORTHEASTERLIES
ANALYZED BEHIND THE PREFRONTAL LINE.
RAIN IS IMMINENT FOR PORTIONS OF THE KEYS FROM NOW UNTIL THE
EVENING HOURS. THE CURRENT LINE OF CONVECTION IS MUCH WEAKER THAN
OBSERVED A FEW HOURS AGO DUE TO A COMBINATION OF FACTORS. ONE OF
WHICH IS THE COOLER WATERS FROM THE SHALLOW NORTHERLY SIDE OF THE
KEYS' NEARSHORE WATERS THAT IS A USUAL REDUCER OF POTENCY FOR
PREFRONTAL LINES. HIGH CLOUD DEBRIS BLOWN OUT AHEAD OF THE LINE
OVER THESE WATERS HINDERED DAYTIME HEATING IN THESE AREAS THUS
REDUCING THE FUEL RESERVES REQUIRED TO SUSTAIN THE LINE EVEN MORE.
CIMSS MIMIC PW ALSO NOTES THAT A SWATH OF DRIER AIR WAS STILL
PRESENT OVER THE KEYS AHEAD OF THE FRONT DESPITE SURFACE DEWPOINTS
IN THE MID 70S. A BETTER SNAPSHOT CAN BE SEEN IN OUR 12Z SOUNDING
FROM THIS MORNING WHERE A LARGE CHUNK OF DRY AIR CAN BE OBSERVED
ABOVE 800 MB. THESE FEATURES SEEM TO HAVE WON OUT AND DAMPENED THE
INTENSITY OF THESE SHOWERS, BUT THE SHARPNESS OF THE ASSOCIATED
TROUGH WILL ALLOW FOR SOME PRECIPITATION TO REACH LAND. RAIN WILL
LIKELY BE SEEN ACROSS PORTIONS OF THE KEYS STARTING WITH THE
LOWER KEYS IN THE NEXT HOUR OR SO.
FOLLOWING THE PASSAGE OF THE DECAYING PREFRONTAL CONVECTIVE LINE,
LOW PRESSURE DEVELOPING OFF THE GEORGIA-SOUTH CAROLINA COASTLINE
WILL DRIVE FRESH TO STRONG BREEZES THROUGH OUR WATERS. AS A
RESULT, A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR ALL COASTAL
WATERS OF THE FLORIDA KEYS. COOLER AND DRIER AIR WILL BLAST
THROUGH FROM THESE NORTHWESTERLIES EFFECTIVELY REDUCING POPS TO
NEAR NIL. SKIES WILL CLEAR THROUGHOUT THE NIGHT ALLOWING
TEMPERATURES TO FALL INTO THE MID 60S AND EVEN A FEW DEGREES
LOWER CLOSER TO MAINLAND IN THE UPPER KEYS.
THE LOW WILL DRIFT OFF INTO THE WESTERN NORTH ATLANTIC ALLOWING BREEZES
TO SLACKEN THROUGH TOMORROW AS HIGH PRESSURE IN THE GULF TAKES
HOLD OF OUR SENSIBLE WEATHER. DRY CONDITIONS WILL PREVAIL
THROUGHOUT THE MID WEEK WITH TEMPERATURES SLOWLY MILDING OUT
TOWARDS THE WEEKEND. SLIGHT CHANCE POPS RETURN AS WINDS SHIFT BACK
TO THE SOUTHEAST BY FRIDAY. GUIDANCE CURRENTLY DEPICTS A DEEP LOW
PRESSURE SYSTEM DEVELOPING IN THE GREAT PLAINS AROUND THIS TIME
WITH IT POSSIBLY INFLUENCING OUR WINDS IN THE EXTENDED FORECAST
DESPITE ITS DISTANCED PASSAGE NORTH. STAY TUNED FOR MORE...
MARINE
ISSUED AT 350 PM EDT MON MAR 10 2025
A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL COASTAL WATERS OF THE
FLORIDA KEYS. FROM SYNOPSIS, AN INTENSIFYING LOW PRESSURE SYSTEM
ALONG THE GULF COAST WILL FORCE A COLD FRONTAL PASSAGE ACROSS THE
FLORIDA KEYS COASTAL WATERS THROUGH MONDAY EVENING. FRESH TO
STRONG NORTHWESTERLY BREEZES IN THE WAKE OF THE FRONT WILL
GRADUALLY SLACKEN ON TUESDAY. HIGH PRESSURE OVER THE GULF WILL
SLIDE EASTWARD THROUGHOUT THE WORK WEEK, WITH GENTLE BREEZES
CLOCKING AROUND TO THE NORTHEAST, THEN EAST, THEN TO THE EAST TO
SOUTHEAST.
AVIATION
(18Z TAFS)
ISSUED AT 350 PM EDT MON MAR 10 2025
A LINE OF SHOWERS WITH A STRAY THUNDERSTORM WILL TRANSIT ACROSS EYW
AND MTH, BRINGING PERIODS OF MVFR, POSSIBLY IFR, CIGS TO BOTH
TERMINALS AFTER 18Z. WINDS WILL RAPIDLY VEER FROM SOUTHWESTERLY TO
NORTHWESTERLY AFTER SHOWERS PASS. GUSTS WILL BE FREQUENT POST
SHOWERS. CROSSWIND CONCERNS WILL BE PRESENT FOR THE FIRST 6 HOURS OF
THE TAF PERIOD. EXPECT CIGS TO GRADUALLY CLEAR OVERNIGHT AFTER THE
FRONT PASSES.
CLIMATE
ON THIS DAY IN 1989, THE DAILY RECORD LOW TEMPERATURE OF 50F WAS
OBSERVED AT MARATHON. TEMPERATURE RECORDS FOR MARATHON DATE BACK TO
1950.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 66 74 67 77 / 10 0 0 0
MARATHON 65 74 67 77 / 20 0 0 0
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 4 AM EDT TUESDAY FOR GMZ031>035-
042>044-052>055-072>075.
PUBLIC/MARINE/FIRE...JAM
AVIATION/NOWCASTS....AJP
DATA ACQUISITION.....DR
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