283
FXUS62 KKEY 090836
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
436 AM EDT SUN MAR 9 2025
..NEW DISCUSSION, MARINE, AVIATION
DISCUSSION
ISSUED AT 430 AM EDT SUN MAR 9 2025
CLEAR SKIES WERE NOTED EARLY
THIS MORNING OVER THE KEYS WITH LIGHT SOUTHERLY WINDS AROUND 5 MPH
OBSERVED OVER THE ISLAND CHAIN. TEMPERATURES WERE STEADY IN THE
LOWER TO MID 70S EXCEPT OVER A FEW SHELTERED INTERIOR LOCATIONS,
WHERE THE BIG PINE KEY DEER NWR RAWS WAS NEAR 65F AND OCEAN REEF
MANAGING TO HOLD STEADY IN THE UPPER 60S.
A SHEARED POSITIVE TILTED MID/UPPER SHORTWAVE TROUGH WAS
PROGRESSING EASTWARD OVER THE SOUTHERN PLAINS TOWARDS THE LOWER
MISSISSIPPI VALLEY WITH A SURFACE LOW SOON TO TAKE SHAPE ALONG A
BAROCLINIC ZONE ACROSS THE NORTHERN GULF COAST. RAPID CHANGES ARE
IN STORE FOR KEYS WEATHER AS THE SURFACE LOW MOVES QUICKLY TO OFF
THE SOUTHEAST U.S. COAST MONDAY. THE ATTENDANT COLD FRONT WILL
APPROACH MONDAY AFTERNOON WITH THE PRESSURE GRADIENT TIGHTENING,
ALLOWING STRENGTHENING SURFACE WINDS OUT OF THE SOUTHWEST, VEERING
WEST AND THEN NORTHWEST AFTER FRONTAL PASSAGE PERHAPS VERY LATE
MONDAY AFTERNOON OR EARLY EVENING. MOISTURE LOOKS SUFFICIENTLY
DEEP TO SUPPORT CONVECTION, ALTHOUGH THE UPPER JET REMAINS TO THE
NORTH WITH POSITIVE VORTICITY ADVECTION LAGGING THE LOWER
TROPOSPHERIC FRONT QUITE A BIT. THERE CONTINUES TO BE SIZABLE
SPREAD IN MONDAY'S RAIN CHANGES IN THE STATISTICAL GUIDANCE. WINDY
AND COOLER CONDITIONS WILL SET IN MONDAY NIGHT. THE FAST
PROGRESSIVE PATTERN WILL ALLOW WINDS TO VEER QUICKLY TO EAST WITH
SURFACE RIDGING PASSING BY TO OUR NORTH.
WITH SHORT-DURATION
COOLER TEMPERATURES AND BREEZY TO WINDY CONDITIONS
FOR THE MEDIUM RANGE, AN IMPRESSIVE UPPER SHORTWAVE TROUGH MOVES
EASTWARD PASSING TO OUR NORTH LATER THIS WORK WEEK, BUT WITH NARY
ANY TIME FOR ANY LOW-TO-MID MOISTURE RETURN. FOR NOW, THIS LOOKS
LIKE A DRY TROUGH PASSAGE ALOFT. DURING THE WEEKEND, UPPER RIDGING
WILL AMPLIFY ALLOWING FOR WARMING TEMPERATURES WITH ANOTHER
IMPRESSIVE TROUGH OVER THE NATION'S MID-SECTION LIFTING MUCH MORE
NORTHWARD.
MARINE
ISSUED AT 430 AM EDT SUN MAR 9 2025
EARLY THIS MORNING, WINDS WERE SOUTHEAST TO SOUTH AROUND 10 KNOTS
ALONG THE REEF AND ESTIMATED 5 TO 10 KNOTS ALONG THE GULF AND
BAYSIDE. SIGNIFICANT WAVE HEIGHT OBSERVED AT SATAN SHOAL WAS
AROUND 1 FOOT WITH A PEAK PERIOD OF 5 SECONDS FROM THE EAST.
LIGHT TO GENTLE MAINLY SOUTH BREEZES ARE EXPECTED TODAY, LULLING
LATE THIS AFTERNOON AND EVENING, BEFORE MODESTLY FRESHENING OUT OF
THE SOUTH TONIGHT. LOW PRESSURE SYSTEM DEVELOPING WHILE MOVING
EASTWARD ALONG THE NORTHERN GULF COAST TODAY WILL RESULT IN A COLD
FRONTAL PASSAGE ACROSS THE FLORIDA KEYS LATE MONDAY WITH GREATER
CONFIDENCE FOR SHOWERS AND THUNDERSTORMS MONDAY AFTERNOON. BREEZES
WILL RAPIDLY VEER FROM SOUTHWESTERLY TO NORTHWESTERLY AND FRESHEN
CONSIDERABLY ACROSS ALL MARINE WATERS. POST COLD FRONT, EXPECT
BREEZES TO SLACKEN TO GENTLE TO MODERATE AND VEER EASTERLY BY MID
WEEK AS HIGH PRESSURE BUILDS OVER THE GULF.
AVIATION
(06Z TAFS)
ISSUED AT 430 AM EDT SUN MAR 9 2025
VFR CONDITIONS WILL PREVAIL AT BOTH EYW AND MTH THROUGH THE TAF
PERIOD. WINDS WILL REMAIN LIGHT AND VARIABLE, BECOMING SOUTHEAST TO
SOUTH BY SUNRISE, THEN VEERING TO THE EAST TO SOUTHEAST BY LATE
AFTERNOON.
CLIMATE
ON THIS DAY IN FLORIDA KEYS WEATHER HISTORY, IN 1998, 3.20" OF RAIN
FELL AT MARATHON. THIS WAS THE THIRD-WETTEST MARCH DAY ON RECORD FOR
MARATHON. RAINFALL RECORDS FOR MARATHON DATE BACK TO 1950.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 82 73 81 66 / 0 20 50 10
MARATHON 82 73 83 64 / 0 10 50 20
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...JR
AVIATION/NOWCASTS....MC
DATA ACQUISITION.....MC
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