795  
FXUS62 KKEY 261738  
AFDKEY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE KEY WEST FL  
138 PM EDT SAT SEP 26 2026  
   
..NEW AVIATION  
 
   
KEY MESSAGES  
 
- SALTWATER FLOODING OF LOW ELEVATION STREETS AND LOTS IS LIKELY  
THROUGH NEXT WEEK DUE TO A POTENT KING TIDE. DON'T DRIVE THROUGH  
FLOODED ROADWAYS. BOATERS CAN EXPECT LESS CLEARANCE UNDER FIXED  
BRIDGES.  
 
- A COASTAL FLOOD STATEMENT IS IN EFFECT FOR THE LOWER TO MIDDLE  
KEYS, AND A COASTAL FLOOD ADVISORY IS IN EFFECT FOR THE UPPER  
KEYS. COASTAL FLOOD ADVISORIES WILL LIKELY BE REQUIRED FOR ALL OF  
THE KEYS BY MONDAY NIGHT.  
 
- INCREASING NORTHEASTERLY SWELL FROM A NOR'EASTER OFF THE EAST  
COAST WILL PRODUCE 4 TO 5 FOOT SEAS THROUGH THE WEEKEND IN THE  
EASTERN STRAITS OF FLORIDA OFF THE UPPER KEYS.  
 
 
   
AVIATION  
 
(18Z TAFS)  
ISSUED AT 138 PM EDT SAT SEP 26 2026  
VFR CONDITIONS WILL PREVAIL AT EYW AND MTH FOR THE UPCOMING TAF  
PERIOD. DRY AIR ALOFT WILL KEEP CLOUD COVER SPARSE, THOUGH  
OCCASIONAL MVFR CIGS ARE POSSIBLE. SHRA ARE PERCOLATING WEST OF  
THE TERMINALS, BUT VCSH CONDITIONS ARE UNLIKELY. NEAR SURFACE  
WINDS ARE ON TRACK TO SHIFT NORTH NORTHWESTERLY AFTER SUNSET.  
 
 
   
PREV DISCUSSION  
 
ISSUED AT 502 AM EDT SAT SEP 26 2026  
A SIGNIFICANTLY DRIER AIRMASS ALOFT CONTINUES TO EXPAND ACROSS  
THE FLORIDA KEYS EARLY THIS AM. BASED ON WATER VAPOR IMAGERY, THE  
COLD FRONT HAS PROGRESSED SLIGHTLY FARTHER SOUTH THAN EXPECTED,  
EXTENDING SOUTH-SOUTHWEST FROM THE PARENT NOR'EASTER SPINNING OFF  
THE MID- ATLANTIC/NEW ENGLAND COAST, THROUGH THE BAHAMAS AND  
ACROSS TO EVEN SLIGHTLY SOUTH OF CUBA. GENTLE TO MODERATE  
NORTHERLY BREEZES WILL CONTINUE ACROSS THE KEYS AND SURROUNDING  
WATERS THIS MORNING, BUT WILL BECOME LIGHT TO GENTLE BY THIS  
AFTERNOON. THE NOR'EASTER WILL REMAIN TRAPPED BETWEEN BROAD  
ATLANTIC RIDGING AND PERSISTENT RIDGING OVER THE CENTRAL CONUS  
BEFORE EVENTUALLY BREAKING DOWN AND EJECTING TOWARDS THE NORTHERN  
ATLANTIC DURING THE MONDAY TO WEDNESDAY TIMEFRAME. IN THE  
MEANTIME, DEEP WEST-NORTHWESTERLY FLOW WILL CONTINUE ACROSS THE  
KEYS THIS WEEKEND AS EMBEDDED SHORTWAVES ROTATE AROUND THE COASTAL  
LOW AND MAINTAIN SOME MEASURE OF CYCLONIC FLOW OVER THE EASTERN  
GULF. WE'RE ALREADY SEEING THE EFFECTS OF THIS WITH ISOLATED  
SHOWERS ONGOING NEAR THE LOWER KEYS AND IN THE STRAITS OF FLORIDA  
DESPITE A DEEP LAYER OF DRY AIR MEASURED ON OUR 00Z RAOB ABOVE  
900MB. MIMIC-TPW IMAGERY SHOWS EVEN DRIER AIR SURGING SOUTH IN THE  
EASTERN GULF. ANY ISOLATED DEVELOPMENT WILL REMAIN RATHER BENIGN  
TODAY AND TOMORROW, AND MOST OF THE DAY WILL FEATURE MOSTLY SUNNY  
SKIES WITH HIGHS IN THE MID TO UPPER 80S. SOME LOCATIONS ALONG THE  
ISLAND CHAIN WILL SEE DEWPOINTS IN THE UPPER 60S TO NEAR 70  
DEGREES ON SUNDAY WHICH WILL DROP HUMIDITY VALUES DOWN INTO THE  
50-60% RANGE.  
 
OUR PRIMARY CONCERN OVER THE NEXT COUPLE OF DAYS AND POTENTIALLY  
INTO NEXT WEEK WILL BE SALTWATER FLOODING OF LOW-LYING AREAS ALONG  
THE KEYS CAUSED BY A PEAK IN ASTRONOMICAL TIDES COMPOUNDED BY A  
BACKED UP GULF STREAM DUE TO THE STRONG NOR'EASTER AND ASSOCIATED  
GALE FORCE WINDS ALONG THE EAST COAST. A COASTAL FLOOD ADVISORY  
HAS BEEN ISSUED FOR THE UPPER KEYS WHILE A COASTAL FLOOD STATEMENT  
REMAINS IN EFFECT FOR THE LOWER TO MIDDLE KEYS THROUGH AT LEAST  
THIS AFTERNOON, BUT EXTENSIONS ARE LIKELY. EVENTUAL UPGRADES MAY  
BE NEEDED FOR THE LOWER/MIDDLE KEYS EARLY NEXT WEEK.  
 
SPEAKING OF NEXT WEEK, IT CERTAINLY LOOKS AS THOUGH OUR BELOW-NORMAL  
RAIN CHANCES WILL BE SHORT-LIVED. ON MONDAY, THE LOWER-LEVELS OF THE  
ATMOSPHERE WILL BECOME INFLUENCED BY ATLANTIC RIDGING WHICH WILL  
EXTEND ACROSS THE KEYS AND PROMOTE A SWITCH BACK TO LOW-LEVEL  
SOUTHERLY FLOW. MEANWHILE TO OUR NORTH, THE CONTINENTAL RIDGE IS  
PROGGED TO RETROGRADE WESTWARD JUST ENOUGH TO ALLOW THE UPPER-LEVEL  
TROUGH ALONG THE COAST TO DEEPEN ACROSS THE SOUTHEAST AND INTO THE  
GULF. BY MONDAY NIGHT, WE'LL SEE A QUICK RESURGENCE IN MOISTURE  
CONTENT WITH INCREASING RAIN AND THUNDER CHANCES. THE MID TO UPPER-  
LEVEL TROUGH WILL CONTINUE TO PROVIDE FORCING ACROSS THE AREA  
THROUGH AT LEAST WEDNESDAY, EVEN AS THE NOR'EASTER BEGINS TO LIFT  
AWAY, LEAVING BEHIND RESIDUAL UPPER-LEVEL TROUGHING ACROSS THE  
FLORIDA PENINSULA TO AS FAR SOUTH AS THE YUCATAN. GLOBAL MODELS  
INDICATE THAT PIECE OF LEFT BEHIND UPPER-LEVEL ENERGY MAY BEGIN TO  
DEEPEN NEAR THE YUCATAN BY THE MIDDLE TO END OF THE WEEK,  
POTENTIALLY SUSTAINING AN ACTIVE PERIOD ACROSS THE FLORIDA KEYS  
THROUGH THE END OF THE FORECAST PERIOD. UNFORTUNATELY, A WET  
FORECAST ON TOP OF KING TIDES MAY EXACERBATE THE FLOODING ISSUES,  
BUT THE DETAILS WILL BE IRONED OUT AS WE GET CLOSER.  
 
 
   
MARINE  
 
ISSUED AT 1032 AM EDT SAT SEP 26 2026  
SHALLOW ISOLATED SHOWERS WILL WAX AND WANE OVER THE WATERS OF THE  
FLORIDA KEYS. MARINE OBSERVATIONS ARE MEASURING GENTLE TO  
MODERATE NORTH TO NORTHEASTERLY BREEZES.  
 
FROM SYNOPSIS: AN EARLY SEASON COLD FRONT WILL REMAIN DRAPED ACROSS THE DISTANT  
STRAITS OF FLORIDA FOR MUCH OF THE WEEKEND, SUPPORTING LIGHT TO  
GENTLE NORTHERLIES. A NOR'EASTER OFF THE EASTERN SEABOARD WILL  
SUPPORT A NORTHEASTERLY SWELL WITH LARGE PERIODS IN THE EASTERN  
MARINE ZONES THROUGH SUNDAY. THE FRONT WILL PUSH BACK NORTHWARD ON  
MONDAY THROUGH THE MARINE ZONES. WINDS WILL THEN CLOCK BACK  
AROUND TO THE SOUTHEAST TO SOUTH FOR EARLY NEXT WEEK, ALSO  
ACCOMPANIED BY INCREASING RAIN AND THUNDER CHANCES.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
KEY WEST 78 87 78 88 / 10 10 10 30  
MARATHON 77 85 78 87 / 10 10 10 30  
 
 
   
KEY WATCHES/WARNINGS/ADVISORIES  
 
FL...COASTAL FLOOD ADVISORY UNTIL 6 AM EDT SUNDAY FOR FLZ076.  
 
GM...NONE.  
 
 
 
 
PUBLIC/MARINE/FIRE...AJP  
AVIATION/NOWCASTS....AJP  
DATA ACQUISITION.....AJP  
 
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