263
FXUS62 KKEY 100830
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
430 AM EDT SAT OCT 10 2026
..NEW DISCUSSION, MARINE, AVIATION
KEY MESSAGES
- A COASTAL FLOOD STATEMENT IS IN EFFECT, AND PARTICULARLY LOW
LYING AREAS WILL SEE SOME SALTWATER PONDING AROUND THE TIMES OF
HIGH TIDE.
- POST-TROPICAL CYCLONE ISAIAS HAS MOVED INLAND INTO SOUTHERN
ALABAMA AFTER MAKING LANDFALL LAST EVENING NEAR DESTIN, FL.
RESIDUAL WESTERLY SWELL WILL CONTINUE TODAY ACROSS THE WESTERN
HALF OF THE COASTAL WATERS.
- ELEVATED RAIN CHANCES ARE EXPECTED BEGINNING THIS AFTERNOON,
PEAKING TONIGHT, BEFORE DECREASING OVER THE REMAINDER OF THE
HOLIDAY WEEKEND.
DISCUSSION
ISSUED AT 430 AM EDT SAT OCT 10 2026
POST-TROPICAL CYCLONE ISAIAS MADE LANDFALL AS A CATEGORY 2
HURRICANE LAST EVENING NEAR DESTIN, FL. THE STORM HAS COMPLETED
ITS EXTRA-TROPICAL TRANSITION AND CONTINUES TO RAPIDLY MOVE
NORTHWARD THROUGH ALABAMA WHILE WEAKENING. TO ITS SOUTH, RIDGING
REMAINS IN PLACE ACROSS THE WESTERN NORTH ATLANTIC WITH THE CENTER
OF THIS RIDGE TO THE NORTH OF PUERTO RICO. THE WESTERN PERIPHERY
OF THIS RIDGE EXTENDS WESTWARD INFLUENCING THE KEYS. MARINE
PLATFORMS SURROUNDING THE ISLAND CHAIN ARE RECORDING MAINLY SOUTH
BREEZES OF 10 TO 15 KNOTS WITH SMITH SHOAL AND SAND KEY RECORDING
15 TO 20 KNOTS. KBYX RADAR WAS ACTIVE EARLIER IN THE EVENING WITH
SHOWERS AND A COUPLE THUNDERSTORMS ACROSS THE OFFSHORE AND
NEARSHORE WATERS OF THE MIDDLE AND UPPER KEYS WHICH WEAKENED ON
APPROACH TO THE CHAIN. A FEW STRONGER CELLS THEN DEVELOPED OVER
FLORIDA BAY WHICH THEN MOVED QUICKLY ONSHORE SOUTH FLORIDA AND
DISSIPATED. TEMPERATURES ALONG THE ISLAND CHAIN ARE STILL VERY
WARM FOR THIS TIME OF THE NIGHT IN THE LOWER TO MID 80S AND DEW
POINTS ARE IN THE UPPER 70S.
FORECAST
TAKING A BIRDS EYE VIEW OF THE WEATHER ACROSS THE SOUTHEAST U.S.,
GULF, AND FLORIDA, WE NOW HAVE POST-TROPICAL CYCLONE ISAIAS OVER
SOUTHERN ALABAMA. POST-TROPICAL CYCLONE ISAIAS WILL CONTINUE TO
RESULT IN ENHANCED W SWELL ACROSS OUR WESTERN WATERS AND SE GULF
TODAY BEFORE SUBSIDING TONIGHT. WE ALSO CONTINUE TO HAVE THE
AFOREMENTIONED RIDGE ABOVE IN THE WESTERN NORTH ATLANTIC ALONG
WITH A STATIONARY FRONT DRAPED ACROSS NORTHERN FLORIDA. THESE
FEATURES CONTINUE TO WORK TOGETHER TO KEEP BREEZES ELEVATED OUT OF
THE SOUTHEAST TO SOUTH. THEREFORE, EXPECT MODERATE TO FRESH
BREEZES TO CONTINUE TODAY, ESPECIALLY ACROSS THE SE GULF AND
WESTERN STRAITS BEFORE MODESTLY SLACKENING LATE TODAY.
WE CONTINUE TO WATCH A WEAK UPPER LEVEL FEATURE WITH INCREASED
MOISTURE MOVING NORTHWESTWARD AS IT RIDES THE WESTERN PERIPHERY OF
THE RIDGE. LATEST GUIDANCE SUGGESTS THE MORNING REMAINING DRY
ACROSS MUCH OF THE KEYS. HOWEVER, AS WE GET DAYTIME HEATING AND
DUE TO THE SOUTH TO SOUTHEASTERLY FLOW, ANY SHOWERS AND
THUNDERSTORMS THAT DEVELOP OVER CUBA THIS AFTERNOON AND EVENING
ARE ANTICIPATED TO MOVE NORTHWARD, POTENTIALLY SPARKING NEW
CONVECTION ACROSS THE KEYS. IT APPEARS ON THE LATEST GUIDANCE THAT
THE LOWER KEYS WESTWARD HAVE THE BEST CHANCE TO SEE SOMETHING
TONIGHT, THOUGH, THAT IS NOT TO SAY SOME SHOWERS OR STORMS CANNOT
OCCUR FURTHER EAST. THE POP CHANCE IS VERY LOW CONFIDENCE WITH
40% IN THE UPPER KEYS TO 50% FOR THE MIDDLE KEYS, AND 60% FOR THE
LOWER KEYS. WE WILL SEE HOW THIS UNFOLDS LATE TODAY AND TONIGHT.
RIDGING IS EXPECTED TO DOMINATE FOR THE SECOND HALF OF THE
HOLIDAY WEEKEND INCLUDING THE HOLIDAY ITSELF. ONE RIDGE WILL BE
OVER THE NORTH ATLANTIC WHILE ANOTHER RIDGE BUILDS IN ACROSS THE
SOUTHEAST U.S. BOTH OF THESE ACTING TOGETHER WILL HELP TO KEEP
BREEZES ELEVATED THROUGH THE PERIOD. THEREFORE, EXPECT EAST TO
SOUTHEAST GENTLE TO MODERATE BREEZES TO CONTINUE THROUGH THIS
PERIOD. DRIER AIR WILL ALSO FILTER INTO THE AREA LEADING TO
DECREASED RAIN CHANCES. EXPECT DAYTIME HIGHS TO REMAIN QUITE WARM
IN THE UPPER 80S AND OVERNIGHT LOWS IN THE LOWER 80S WITH DEW
POINTS POTENTIALLY HOVERING NEAR 80 DEGREES THROUGH THIS PERIOD.
VERY WARM AND TROPICAL FOR CONSIDERING WE ARE APPROACHING MID-
OCTOBER AT THIS POINT.
NUMERICAL AND GLOBAL MODEL GUIDANCE CONTINUES TO SHOW A FRONT
PRESSING THROUGH THE KEYS SOMETIME TUESDAY/TUESDAY NIGHT.
CONFIDENCE CONTINUES TO GROW FOR A POTENTIAL DIP IN DEW POINTS
TOWARDS MID WEEK AND SLIGHTLY COOLER TEMPERATURES. DEW POINTS
POTENTIALLY DOWN TO THE LOWER 70S, OR 70 DEGREES? IT ALSO APPEARS
LIKE THIS FRONT WILL PRESS THROUGH WHICH MAY RESULT IN NEAR NIL
RAIN CHANCES FOR A FEW FORECAST PERIODS BEFORE LIFTING BACK NORTH
AS A WARM FRONT LATER IN THE WEEK WITH A RETURN TO MUGGIER AND
POTENTIALLY WETTER CONDITIONS.
MARINE
ISSUED AT 430 AM EDT SAT OCT 10 2026
SMALL CRAFT SHOULD EXERCISE CAUTION (SCEC) UNTIL WINDS DECREASE
AND SEAS SUBSIDE ARE HEADLINED FOR TODAY ACROSS THE SE GULF WATERS
AND THE WESTERNMOST FL STRAITS. FOR THE NEARSHORE WATERS
SURROUNDING THE LOWER KEYS, SMALL CRAFT SHOULD EXERCISE CAUTION
UNTIL WINDS DECREASE IS HEADLINED. BOATERS SHOULD BE AWARE OF LESS
CLEARANCE UNDER FIXED BRIDGES AROUND TIMES OF HIGH TIDE AS A
COASTAL FLOOD STATEMENT IS IN EFFECT FOR THE FLORIDA KEYS. FROM
SYNOPSIS, POST-TROPICAL CYCLONE ISAIAS MADE LANDFALL LAST EVENING
NEAR DESTIN, FL. THE STORM CONTINUES TO MOVE RAPIDLY NORTHWARD
WHILE WEAKENING. MODERATE TO FRESH SOUTHEAST TO SOUTH BREEZES ARE
EXPECTED TO CONTINUE THROUGHOUT THE FLORIDA KEYS COASTAL WATERS,
ESPECIALLY THE SE GULF, WESTERN STRAIT, AND THE NEARSHORE WATERS
SURROUNDING THE LOWER KEYS TODAY. ELEVATED SWELLS WILL PERSIST
THROUGH THE WESTERN FL STRAITS TODAY AND THE SE GULF WATERS TODAY.
BREEZES WILL ONLY MODESTLY SLACKEN TO GENTLE TO MODERATE AS THE
CYCLONE CONTINUES TO MOVE AWAY AND RIDGING BUILDS IN BEHIND IT.
MEANWHILE, A PLUME OF MOISTURE WILL MOVE THROUGH THE KEYS TODAY
THROUGH TONIGHT WITH AN INCREASE IN SHOWER AND THUNDERSTORM
COVERAGE, ESPECIALLY TONIGHT. THEREAFTER, A FRONTAL BOUNDARY MAY
PUSH THROUGH THE REGION EARLY NEXT WEEK PROMOTING NORTHEAST
BREEZES.
AVIATION
(06Z TAFS)
ISSUED AT 430 AM EDT SAT OCT 10 2026
VFR CONDITIONS ARE EXPECTED TO PERSIST AT BOTH EYW AND MTH
TERMINALS THROUGH THE TAF PERIOD. NEAR SURFACE WINDS WILL REMAIN
MAINLY SOUTHERLY THIS MORNING INTO THE AFTERNOON BEFORE SHIFTING
TO THE SOUTHEAST FOR THE EVENING AND OVERNIGHT HOURS. IN ADDITION,
WHILE MOST OF THE MORNING LOOKS TO REMAIN DRY, CONVECTION IS
ANTICIPATED TO DEVELOP NEAR CUBA AND THEN MOVE NORTHWARD TOWARDS
THE ISLAND CHAIN SOMETIME THIS AFTERNOON WITH THE THREAT
CONTINUING THROUGH THE OVERNIGHT. THE BEST CHANCE TIME FOR THIS
APPEARS TO BE AFTER 11/00Z, THOUGH, WE CAN'T RULE OUT ACTIVITY
BEFORE THIS TIME THAT MAY IMPACT THE TERMINALS. DUE TO AVERAGE
CONFIDENCE ON TIMING AND PLACEMENT, VCSH WAS PLACED INTO THE TAF
FOR THIS EVENING.
CLIMATE
ON THIS DAY ON 2009, THE DAILY RECORD WARM LOW TEMPERATURE OF 84F
WAS RECORDED IN KEY WEST. TEMPERATURE RECORDS FOR KEY WEST DATE
BACK TO 1872. ALSO, ON THIS DAY IN 1975, THE DAILY RECORD WARM LOW
TEMPERATURE OF 83F WAS RECORDED IN MARATHON. TEMPERATURE RECORDS
FOR MARATHON DATE BACK TO 1951.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 89 83 89 83 / 10 60 20 10
MARATHON 89 81 89 81 / 10 50 20 10
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...MJV
AVIATION/NOWCASTS....MJV/JR
DATA ACQUISITION.....MJV
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