727
FXUS62 KKEY 091916
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
316 PM EDT WED APR 9 2025
..NEW DISCUSSION, MARINE, AVIATION
DISCUSSION
ISSUED AT 315 PM EDT WED APR 9 2025
AN INTERESTING AFTERNOON HAS UNFOLDED ACROSS THE FLORIDA KEYS,
ESPECIALLY IN REGARDS TO THE WIND. MARINE PLATFORMS AROUND THE
KEYS HAVE RANGED WIDELY FROM CALM CONDITIONS FOR A TIME EARLIER
THIS AFTERNOON AT LONG KEY TO BLOWING NEAR 20 KNOTS AT SAND KEY
AND 10 TO 15 KNOTS AT CARYSFORT REEF LIGHT. SOME CATALYSTS THAT
WERE SURMISED TO BE A FACTOR IN WHY THE DISPARITY IN THE WIND IS
AS FOLLOWS. WE HAVE LOW PRESSURE DEVELOPING NORTH OF THE BAHAMAS
AND A HIGH PRESSURE SYSTEM OVER THE GULF. THIS IS CREATING FOR
CYCLONIC FLOW ACROSS FLORIDA WITH NORTHWEST TO NORTH FLOW BETWEEN
THE TWO. IN ADDITION, ADD IN HEATING OF THE FLORIDA MAINLAND
THROUGHOUT THE DAY, WHICH INDUCES A THERMAL LOW AND WE HAD THE
WINDS COLLAPSE ACROSS FLORIDA BAY AND JUST EAST OF MARATHON. AS
OF THE LAST OBSERVATION EVEN MARATHON WAS GUSTING AS HIGH AS 25
MPH. THEREFORE, JUST ENOUGH OF THE MIDDLE KEYS IS EXPOSED TO ALL
WATER TO THE NORTH NOT ALLOWING FOR MUCH FRICTION, WHEREAS LONG
KEY IS TUCKED IN JUST ENOUGH TO BE PROTECTED SOME BY THE MAINLAND
UNDER NORTHWEST TO NORTH FLOW. HOWEVER, A SUBTLE WIND SHIFT TO
MORE NORTHWESTERLY HAS NOW OCCURRED IN THE PAST HOUR AND LONG KEY
HAS INCREASED TO 10 TO 15 KNOTS. TEMPERATURES ALONG THE ISLAND
CHAIN ARE IN THE MID TO UPPER 70S ACROSS THE UPPER AND LOWER KEYS
WITH LOWER TO MID 70S FOR THE MIDDLE KEYS. GOES 16 VISIBLE
SATELLITE ALSO SHOWS MOST OF THE CLOUD COVER CONTINUING TO MOVE
AWAY FROM THE AREA WITH JUST SOME FAIR WEATHER CUMULUS CLOUDS
LEFTOVER.
FORECAST
THE PATTERN FOR TONIGHT THROUGH FRIDAY WILL MOSTLY RESEMBLE HIGH
PRESSURE OVER THE GULF WITH LOW PRESSURE TO THE NORTH OF THE
BAHAMAS. AS A RESULT, DUE TO DAYTIME HEATING OF THE FLORIDA
MAINLAND AND A THERMAL LOW TRYING TO FORM, BREEZY CONDITIONS ARE
EXPECTED TO ABATE A BIT FOR THURSDAY LATE MORNING AND AFTERNOON
BEFORE RAMPING UP ONCE AGAIN FOR THURSDAY NIGHT DUE TO THE
NOCTURNAL SURGE AND LAND BREEZE OFF THE MAINLAND, THOUGH THIS
INCREASE WON'T BE NEARLY AS PREVALENT AS LAST NIGHT AND TONIGHT.
THIS WILL CONTINUE TO BE THE THEME FOR FRIDAY AS WELL. ALSO, THE
LOW TO THE NORTH OF THE BAHAMAS WILL CONTINUE TO FUNNEL MOISTURE
SOUTHWARD ALONG ITS WESTERN FLANK RESULTING IN SLIGHT CHANCES OF
RAIN FOR THURSDAY THROUGH THURSDAY NIGHT. THIS WILL ESPECIALLY BE
TRUE FOR THE UPPER KEYS.
ANOTHER FRONT IS EXPECTED TO PRESS THROUGH THE KEYS SOMETIME LATE
IN THE WEEK OR EARLY IN THE WEEKEND. THIS WILL RESULT IN
DECREASING HUMIDITY AND SLIGHTLY COOLER TEMPERATURES AGAIN ALONG
WITH MUCH DRIER AIR LENDING TO NEAR NIL RAIN CHANCES. THE COOL DAY
IS EXPECTED TO BE SUNDAY WHERE DEW POINTS MAY FALL INTO THE LOWER
TO MID 50S WITH DAYTIME HIGHS IN THE UPPER 70S AND OVERNIGHT LOWS
IN THE LOWER TO MID 60S.
IN THE WAKE OF THE FRONTAL PASSAGE OVER THE WEEKEND, HIGH PRESSURE
BUILDS AND SLIDES ACROSS THE NORTH GULF COAST. PLENTY OF DRY AIR
IS EXPECTED TO ACCOMPANY THIS HIGH RESULTING IN NEAR NIL RAIN
CHANCES THROUGH FOR THE EARLY TO MIDDLE PART OF NEXT WEEK.
TEMPERATURES WILL START BELOW SEASONABLE LEVELS WITH SLOW
MODERATION EXPECTED EACH DAY NEXT WEEK ALONG WITH HUMIDITY
REMAINING COMFORTABLE.
MARINE
ISSUED AT 315 PM EDT WED APR 9 2025
A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THE FLORIDA KEYS
COASTAL WATERS TONIGHT, EXCEPT FOR THE FLORIDA BAY, EASTERN HAWK
CHANNEL, AND THE EASTERN STRAITS OF FLORIDA. SMALL CRAFT SHOULD
EXERCISE CAUTION (SCEC) FOR INCREASING WINDS IS HEADLINED TONIGHT
FOR FLORIDA BAY, EASTERN HAWK CHANNEL, AND THE EASTERN STRAITS OF
FLORIDA. FROM SYNOPSIS, WIDELY RANGING NORTHWEST TO NORTH BREEZES
THROUGHOUT THE FLORIDA KEYS COASTAL WATERS ARE EXPECTED TO
FRESHEN ACROSS MOST OF THE AREA HEADING INTO TONIGHT. THE
EXCEPTION WILL BE THE EASTERNMOST MARINE AREAS WHERE THEY MAY BE
SHADOWED BY THE FLORIDA MAINLAND RESULTING IN SMALL CRAFT SHOULD
EXERCISE CAUTION HEADLINES. HIGH PRESSURE OVER THE GULF AND LOW
PRESSURE TO NORTH OF THE BAHAMAS WILL RESULT IN PEAKING AND
LULLING BREEZES CONTINUING THROUGH EARLY FRIDAY. ANOTHER FRONTAL
PASSAGE MAY PRESS THROUGH THE KEYS LATE WEEK OR EARLY IN THE
WEEKEND WITH ANOTHER ROUND OF FRESHENING NORTHWEST TO NORTH
BREEZES.
AVIATION
(18Z TAFS)
ISSUED AT 315 PM EDT WED APR 9 2025
VFR CONDITIONS PREVAIL AT EYW AND MTH FOR THE 18Z TAF PERIOD.
CLOUDS ARE GRADUALLY DISSIPATING TONIGHT AS WINDS SURGE TO NEAR 15
KNOTS WITH FREQUENT GUSTS UP TO 25 KNOTS. SUSTAINED NORTHERLIES
WILL BE THE MAIN CONCERN, BECAUSE BREEZES ARE NOT FORECAST TO
SLACKEN UNTIL TOMORROW MORNING. WINDS WILL ALSO VEER TO BE ALMOST
DIRECT CROSSWINDS TONIGHT, MAINLY IN THE PRE DAWN HOURS. LITTLE IF
ANY CHANCE OF RAINFALL IS EXPECTED IN THE EYW AND MTH AIRSPACE.
CLIMATE
ON THIS DAY IN 1985, THE DAILY RECORD OF 2.64" OF RAIN FELL AT
KEY WEST. RAINFALL RECORDS FOR KEY WEST DATE BACK TO 1871.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 69 79 72 79 / 0 10 20 10
MARATHON 69 80 72 81 / 0 10 20 10
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 5 AM EDT THURSDAY FOR GMZ032>035-043-
044-053>055-073>075.
PUBLIC/MARINE/FIRE...MJV
AVIATION/NOWCASTS....AJP
DATA ACQUISITION.....AJP
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