818  
FXUS62 KKEY 181859  
AFDKEY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE KEY WEST FL  
259 PM EDT MON AUG 18 2025  
   
..NEW AVIATION, MARINE
 
 
   
AVIATION
 
 
(18Z TAFS)  
ISSUED AT 300 PM EDT MON AUG 18 2025  
VFR CONDITIONS WILL PREVAIL FOR THE REST OF THE DAY AND INTO  
TONIGHT. A PASSING SHOWER OR TWO CANNOT BE RULED OUT ESPECIALLY  
NEAR MTH WHERE STORMS MAY DESCEND SOUTH FROM MAINLAND FLORIDA.  
HOWEVER, VCSH IS NOT MENTIONED IN EITHER TAF DUE TO LOW CONFIDENCE  
OF OCCURENCE AND EXACT TIMING OF STILL DEVELOPING PRECIPITATION.  
NEAR SURFACE WINDS WILL BE LIGHT AND GENERALLY OUT OF THE  
NORTHWEST TO NORTH.  
 

 
   
PREVIOUS DISCUSSION
 
 
ISSUED AT 1115 AM EDT MON AUG 18 2025  
A FAIRLY CALM AND CLEAR DAY IS UNDERWAY ACROSS THE FLORIDA KEYS.  
FOLLOWING A FEW SPECKS OF SHALLOW NOCTURNAL SHOWERS THIS MORNING,  
KBYX IS CURRENTLY FREE OF ANY PRECIPITABLE ECHOES IN OUR AREA,  
MINUS ONE SHOWER OVER THE MARQUESAS KEYS. EVEN GOES-19 VISIBLE  
IMAGERY IS SHOWING MOSTLY CLEAR SKIES OVER THE ISLAND CHAIN AND  
ITS NEARSHORE WATERS WITH ONLY A CLUSTER OF FAIR WEATHER CU HERE  
AND THERE. SOME CLOUDS HAVE STARTED BUILDING MORE RECENTLY OVER  
THE LOWER KEYS, BUT NOTHING STANDS OUT FROM THE CROWD JUST YET.  
TEMPERATURES ARE ALREADY APPROACHING NEAR 90 ACROSS THE KEYS AS A  
RESULT. THIS ALONG WITH LIGHT AND VARIABLE WINDS, IS MAKING IT  
FEEL LIKE A SOMEWHAT TYPICAL SUMMER DAY.  
 
WHAT IS NOT TOO NORMAL ABOUT TODAY IS THE SURROUNDING SYNOPTIC  
FEATURES. A COL REGION IS CURRENTLY OVER THE KEYS PROMOTING LIGHT  
AND VARIABLE BREEZES BETWEEN DEEP RIDGING OVER SOUTHEAST CONUS  
AND HURRICANE ERIN CURRENTLY LOCATED 110 MILES NORTH OF GRAND TURK  
ISLAND. OVER THE SHORT TERM FORECAST, ERIN IS PROGGED TO CONTINUE  
NORTHWEST PASSING TO THE EAST OF THE BAHAMAS KEEPING THE FLORIDA  
KEYS FROM ANY DIRECT IMPACTS. IT WILL, HOWEVER, STILL HAVE  
SOMEWHAT OF A PULL ON OUR SENSIBLE WEATHER. CIMSS MIMIC LAYER TPW  
SHOWS THAT THE DRY SLOT IN FRONT OF ERIN IS CURRENTLY OVER OUR  
AREA. THIS MORNING'S KKEY 12Z SOUNDING MEASURED A PW OF 1.65  
INCHES WHICH IS JUST BELOW THE 25TH PERCENTILE. THIS NOTABLY DRY  
LAYER FOUND IN THE LOWER TO MID LEVELS OF THE SOUNDING WILL HINDER  
CONVECTIVE DEVELOPMENT AROUND OUR CWA TODAY. THE BEST CHANCE FOR  
RAIN TODAY, IF ANY, WILL BE FROM MAINLAND SOUTH FLORIDA ONCE THEIR  
USUAL ROUND OF AFTERNOON CONVECTION BUILDS UP AND OUR WINDS SHIFT  
TO BE OUT OF THE NORTHWEST TO NORTH DUE TO ERIN'S INFLUENCE. THUS  
HAVE ELECTED TO LOWER POPS TO SLIGHT CHANCE FOR THIS AFTERNOON  
YET STILL JUST ABOVE RECENT GUIDANCE CONSIDERING THE TIME OF YEAR.  
 

 
   
FORECAST
 
 
ISSUED AT 427 AM EDT MON AUG 18 2025  
WHILE HURRICANE ERIN IS NOT EXPECTED TO CAUSE ANY DIRECT IMPACTS  
TO THE FLORIDA KEYS, SYNOPTICALLY IT WILL BE THE MAIN FEATURE FOR  
THE NEXT FEW DAYS. AS ERIN MOVES NORTHERLY FAR TO OUR EAST, WINDS  
WILL BE NORTHWEST AND EVENTUALLY WESTERLY WHICH IS NOT TYPICAL  
FOR OUR CWA. THIS WON'T LAST LONG AS THE SYSTEM CONTINUES TO MOVE  
FURTHER FROM THE US. THEN SYNOPTIC INFLUENCES WILL LACK IN THE  
REGION AND WINDS WILL SHIFT BACK TO THEIR EASTERLY DIRECTION AND  
RAIN CHANCES WILL REMAIN NEAR NORMAL. STAY TUNED FOR ANY UPDATES.  
 

 
   
MARINE
 
 
ISSUED AT 300 PM EDT MON AUG 18 2025  
NO WATCHES, WARNINGS, OR ADVISORIES ARE CURRENTLY IN EFFECT FOR  
THE COASTAL WATERS OF THE FLORIDA KEYS. FROM SYNOPSIS, THE KEYS  
ARE IN A COL REGION BETWEEN RIDGING OVER THE SOUTHEAST US AND  
HURRICANE ERIN IN THE WESTERN NORTH ATLANTIC RESULTING IN NOW  
LIGHT TO GENTLE NORTHWEST TO NORTHERLY BREEZES ACROSS OUR WATERS.  
AS HURRICANE ERIN MAKES ITS CLOSEST POINT OF APPROACH EAST OF THE  
BAHAMAS, BREEZES WILL VEER TO THE NORTHWEST TO NORTH AND FRESHEN  
BY TONIGHT BEFORE GRADUALLY BACKING TO THE SOUTH BY THE END OF THE  
WEEK.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
KEY WEST 82 93 82 92 / 30 30 40 30  
MARATHON 82 91 82 91 / 30 30 30 30  
 

 
   
KEY WATCHES/WARNINGS/ADVISORIES
 
 
FL...NONE.  
GM...NONE.  

 
 

 
 
PUBLIC/MARINE/FIRE...JAM  
AVIATION/NOWCASTS....JAM  
DATA ACQUISITION.....JAM  
 
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