372
FXUS62 KKEY 090836
AFDKEY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
436 AM EDT FRI OCT 9 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.
- INCREASING MOISTURE ACROSS THE KEYS TODAY THROUGH SATURDAY NIGHT
WILL LEAD TO HIGHER RAIN CHANCES, PEAKING TONIGHT.
- HURRICANE ISAIAS IN THE GULF DOES NOT POSE A DIRECT THREAT TO
THE FLORIDA KEYS, BUT IT WILL BRING INCREASING WESTERLY SWELL
INTO THE REGION TODAY AND TONIGHT.
DISCUSSION
ISSUED AT 433 AM EDT FRI OCT 9 2026
CIMSS PRODUCTS SHOWS 3 FEATURES OF NOTE EARLY THIS MORNING
INFLUENCING THE WEATHER ACROSS THE KEYS. FIRST AND FOREMOST, WE
HAVE HURRICANE ISAIAS WHICH IS CLOSING IN ON MAJOR HURRICANE
STRENGTH AS IT CONTINUES TO MOVE NORTHEASTWARD ACROSS THE CENTRAL
GULF TOWARDS THE NORTH GULF COAST. SECOND, THERE IS A STRONG RIDGE
OVER THE WESTERN NORTH ATLANTIC CENTERED TO THE NORTH OF THE
LESSER ANTILLES. THIRD, THERE IS ANOTHER WEAKER RIDGE IN PLACE
ACROSS THE ARK-LA-TEX REGION. AT THE SURFACE, THE WESTERN
PERIPHERY OF THE HIGH ACROSS THE ATLANTIC IS HOLDING STRONG ACROSS
THE KEYS. MARINE PLATFORMS SURROUNDING THE ISLAND CHAIN ARE
RECORDING SOUTHEAST TO SOUTH BREEZES OF 10 TO 15 KNOTS WITH NEAR
15 KNOTS ACROSS THE PLATFORMS SURROUNDING THE LOWER KEYS. KBYX
RADAR SHOWED SOME SHOWER AND THUNDERSTORM EARLIER IN THE NIGHT
THAT RACED NORTHWARD ACROSS THE WESTERNMOST WATERS, INCLUDING THE
DRY TORTUGAS. HOWEVER, THIS ACTIVITY HAS SINCE MOVED OUTSIDE OF
THE FLORIDA KEYS WATERS AND ARE NOW ACROSS THE MARINE WATERS TO
THE WEST OF SOUTHWEST FLORIDA. THOUGH, IN THE LAST 15-20 MINUTES
AROUND 330 AM, SOME NEW ACTIVITY WAS STARTING TO DEVELOP ACROSS
THE SE GULF NEAR L TO T TOWER. ADDITIONALLY, A FEW BRIEF SHOWERS
DEVELOPED ACROSS THE DISTANT STRAITS SOUTH OF THE LOWER KEYS AND
WERE STILL ONGOING AS OF 330 AM. TEMPERATURES ALONG THE ISLAND
CHAIN ARE 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 CONTINUE TO HAVE HURRICANE ISAIAS OVER THE
CENTRAL GULF. ISAIAS WILL CONTINUE TO MOVE NORTHWARD TODAY MAKING
LANDFALL SOMEWHERE ALONG THE FLORIDA PANHANDLE IN THE VICINITY OF
PENSACOLA THIS EVENING INTO THE OVERNIGHT PERIOD. ALL THIS TO SAY,
ISAIAS CONTINUES TO NOT POSE A THREAT TO THE KEYS OUTSIDE OF SOME
ENHANCED SWELL AFFECTING OUR WESTERNMOST WATERS, ESPECIALLY THE
SE GULF AND THE WESTERN STRAITS OF FLORIDA. WE ALSO CONTINUE TO
HAVE THE AFOREMENTIONED RIDGE ABOVE IN THE WESTERN NORTH ATLANTIC
ALONG WITH A STATIONARY FRONT DRAPED ACROSS CENTRAL FLORIDA. THESE
FEATURES ALL ACTING IN TANDEM WITH ONE ANOTHER WILL CREATE FOR AN
INCREASED PRESSURE GRADIENT ACROSS THE REGION TODAY. THEREFORE,
EXPECT MODERATE TO FRESH SOUTHEAST TO SOUTH BREEZES TO CONTINUE
TODAY AND TONIGHT.
THE NEXT ITEM OF INTEREST WILL BE A CURRENT PERTURBATION OR
INVERTED TROUGH NEAR CENTRAL CUBA. CIMSS MIMIC TPW- (TOTAL
PRECIPITABLE WATER) PRODUCTS SHOWS ALSO DRASTICALLY INCREASED
MOISTURE IN THIS REGION. THIS FEATURE WILL CONTINUE TO TREK
NORTHWESTWARD AROUND THE PERIPHERY OF THE HIGH IN THE ATLANTIC.
THIS ENERGY IS EXPECTED TO REACH THE KEYS SOMETIME LATE TODAY AND
TONIGHT RESULTING IN ANOTHER UPTICK IN MOISTURE AND THUS RAIN AND
THUNDER CHANCES. CURRENTLY ADVERTISING 40% FOR TODAY AND 60% FOR
TONIGHT. SINCE THIS FEATURE WILL HAVE NO WHERE TO GO DUE TO THE
FRONTAL BOUNDARY THAT IS STILL DRAPED ACROSS FLORIDA, WE EXPECT
THE MOISTURE TO GET STRUNG OUT ACROSS THE KEYS FOR SATURDAY AND
SATURDAY NIGHT KEEPING ELEVATED RAIN CHANCES, CURRENTLY AT 40%. IN
ADDITION, GENTLE TO MODERATE SOUTHEAST BREEZES WILL CONTINUE
THROUGH THIS PERIOD.
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 IS COMING INTO BETTER
AGREEMENT ON A FRONT TO PRESS THROUGH THE KEYS SOMETIME
TUESDAY/TUESDAY NIGHT. CONFIDENCE IS GROWING 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? COULD
THERE BE POTENTIAL RELIEF FROM THE HUMIDITY TO TAKE THE EDGE OFF
AS WE NEAR THE MIDDLE OF OCTOBER? WE WILL CONTINUE TO FINE TUNE
THIS IN THE COMING DAYS. 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 433 AM EDT FRI OCT 9 2026
SMALL CRAFT SHOULD EXERCISE CAUTION (SCEC) ARE HEADLINED FOR THE
SE GULF WATERS AS WELL AS THE WESTERNMOST STRAITS OF FLORIDA.
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, HURRICANE ISAIAS WILL
MOVE TOWARDS THE NORTHERN GULF COAST THROUGH TONIGHT,
STRENGTHENING AS IT DOES SO. ENHANCED SWELL GENERATED BY THIS
SYSTEM WILL INCREASE WAVE HEIGHTS IN THE WESTERN FLORIDA STRAITS
AND GULFSIDE WATERS TODAY THROUGH THE FIRST HALF OF THE WEEKEND. A
STATIONARY FRONT REMAINS DRAPED ACROSS NORTH- CENTRAL FLORIDA
INFRINGING ON THE SURFACE RIDGE TO ITS SOUTH. THIS WILL CONTINUE
TO PROMOTE MODERATE TO FRESH BREEZES, ESPECIALLY ACROSS THE
WESTERN WATERS TODAY THROUGH AT LEAST EARLY SATURDAY BEFORE
MODESTLY SLACKENING. A PLUME OF MOISTURE WILL ALSO MOVE INTO THE
FLORIDA KEYS AT THE SAME TIME AND INCREASE SHOWER AND THUNDERSTORM
CHANCES.
AVIATION
(06Z TAFS)
ISSUED AT 433 AM EDT FRI OCT 9 2026
VFR CONDITIONS ARE EXPECTED TO PERSIST AT BOTH EYW AND MTH
TERMINALS THROUGH THE TAF PERIOD. NEAR SURFACE WINDS ARE EXPECTED
TO REMAIN MOSTLY SOUTHEAST TO SOUTH THROUGH THE TAF PERIOD. WHILE
THERE IS THE RISK FOR A FEW PASSING SHOWERS OR THUNDERSTORMS
DURING THE DAY, THE BETTER RISK WILL BE MAINLY AFTER 10/03Z
TONIGHT CONTINUING THROUGH THE OVERNIGHT HOURS. ANY SHOWERS OR
STORMS WILL BE CAPABLE OF REDUCING CIGS AND VIS, PRODUCE GUSTY
WINDS, AND THE POTENTIAL FOR A FEW LIGHTNING STRIKES.
CLIMATE
ON THIS DAY IN 2009, THE DAILY RECORD WARM LOW TEMPERATURE OF 84F
WAS RECORDED IN KEY WEST. TEMPERATURE RECORDS FOR KEY WEST DATE
BACK TO 1872. ON THIS DAY IN 2009, THE DAILY RECORD WARM LOW
TEMPERATURE OF 83F WAS RECORDED IN MARATHON. TEMPERATURE RECORDS
FOR MARATHON DATE BACK TO 1951.
OF NOTE
AT PENNEKAMP STATE PARK: IN 2011, A RAINFALL OF 11.02" WAS RECORDED.
PRELIMINARY POINT TEMPS/POPS
KEY WEST 88 82 88 82 / 30 60 40 60
MARATHON 88 81 89 82 / 50 50 30 40
KEY WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GM...NONE.
PUBLIC/MARINE/FIRE...MJV
AVIATION/NOWCASTS....MJV
DATA ACQUISITION.....MJV
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