908  
FXUS62 KKEY 090830  
AFDKEY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE KEY WEST FL  
430 AM EDT TUE SEP 9 2025  
   
..NEW DISCUSSION, MARINE, AVIATION  
 
   
DISCUSSION  
 
ISSUED AT 231 AM EDT TUE SEP 9 2025  
 
BROAD MID TO UPPER LEVEL TROUGHING BLANKETING EASTERN NORTH  
AMERICA REACHES SOUTHWARD INTO THE GULF THIS MORNING. WITH THAT  
SAID, A SHORTWAVE TROUGH IS LIFTING OUT ACROSS NEW ENGLAND AND IS  
YANKING OUT THE EASTERN HALF OF A PERSISTENT SURFACE TROUGH  
STRADDLING THE FLORIDA PENINSULA. AT LEAST FOR TODAY, THE WESTERN  
HALF OF THIS TROUGH WILL REMAIN BALLED UP IN THE EASTERN GULF AND  
CONTRIBUTE TO A MOIST AND CONFLUENT ZONE ACROSS FLORIDA AND THE  
KEYS. SUPPORT ALOFT IS EXPECTED TO BE NEUTRAL. WITH THAT SAID,  
SOME GUIDANCE SUGGESTS THE STEERING FLOW WILL VEER FURTHER  
SOUTHWEST. THIS AGAINST THE BACK DROP OF A MOIST AND CONFLUENT  
BOUNDARY LAYER WILL RESULT IN A HEIGHTENED POTENTIAL FOR SHOWERS  
AND THUNDERSTORMS. WILL ADVERTISE LIKELY POPS FOR TODAY.  
 
THE ATLANTIC RIDGE WILL MAKE A BRAVE ATTEMPT TO SWING  
NORTHWESTWARD INTO THE KEYS TONIGHT AS SURFACE TROUGH TO OUR NORTH  
LIFTS A BIT TO THE NORTH AND WEAKENS. GUIDANCE SUGGESTS SOME  
DRYING AND STABILIZATION WILL OCCUR AND HELP BAT RAIN CHANCES DOWN  
TO NEAR NORMAL. WITH THAT SAID, SHUT DOWN IS NOT EXPECTED AS  
MOISTURE AND INSTABILITY IS EXPECTED TO REMAIN AMPLE AND THE WEAK  
FLOW WILL ALLOW FOR THE USUAL MESOSCALE AND DIURNAL TRIGGERS. THE  
LOWER LEVEL RIDGE WILL REMAIN ACROSS OUR AREA AFTER MID WEEK.  
MOISTURE WILL REMAIN HIGH, AS WILL CAPE, KEEPING RAIN CHANCES NEAR  
TO SLIGHTLY ABOVE NORMAL.  
 
UNCERTAINTY RAMPS UP CONSIDERABLY LATER IN THE WEEK AND WEEKEND.  
GUIDANCE SUGGESTS A STAGNANT FRONT THAT HAS BEEN DRAPED ACROSS  
NORTH AND CENTRAL FLORIDA FOR AN ETERNITY WILL BEGIN ADVANCING  
SOUTHWARD INTO SOUTH FLORIDA ON FRIDAY AND POSSIBLY INTO THE KEYS  
THIS WEEKEND. THIS WILL BE DRIVEN BY A COMPLICATED  
REAMPLIFICATION OF THE MID LATITUDE TROUGH STILL SITTING OVER THE  
EASTERN UNITED STATES. ONE MODEL SOLUTION SUGGESTS A PREFRONTAL  
TROUGH WILL PUSH THROUGH THE KEYS THIS WEEKEND. ANY SORT OF MID  
LATITUDE PUSH THIS TIME OF YEAR USUALLY RESULTS IN A VERY WET  
STRETCH. FOR NOW WILL MAINTAIN CURRENT FORECAST TRENDS WITH POPS  
CLIMBING TO LIKELY BY FRIDAY AND PERSISTING INTO THE WEEKEND.  
 
 
   
MARINE  
 
ISSUED AT 231 AM EDT TUE SEP 9 2025  
 
A DOUBLE BARRELED LOW STRADDLING THE FLORIDA PENINSULA THIS  
MORNING IS EXPECTED TO PULL NORTHWARD AND FURTHER AWAY FROM THE  
KEYS OVER THE NEXT DAY OR TWO. AT LEAST FOR TODAY, KEYS WATERS  
WILL REMAIN IN A FAIRLY MOIST AND CONFLUENT ZONE AROUND THE GULF  
LOW'S SOUTHEASTERN PERIPHERY. CONSEQUENTLY, EXPECT PERIODS OF  
ABOVE NORMAL CONVECTIVE COVERAGE TODAY, PARING BACK TO NEAR OR  
SLIGHTLY ABOVE NORMAL TODAY. WINDS WILL GENERALLY REMAIN LIGHT OUT  
OF THE SOUTH TO SOUTHWEST BUT WITH PERIODS OF VARIABILITY. A  
SLOPPY PRESSURE FIELD WILL PREVAIL THROUGH MID WEEK, RESULTING IN  
LIGHT AND OFTEN VARIABLE BREEZES. A FRONT IS EXPECTED TO SAG  
SOUTHWARD DOWN THE FLORIDA PENINSULA LATER IN THE WEEK, RESULTING  
IN MORE CONSISTENT LIGHT TO GENTLE NORTHEASTERLY BREEZES.  
 
 
   
AVIATION  
 
(06Z TAFS)  
ISSUED AT 231 AM EDT TUE SEP 9 2025  
 
VFR CONDITIONS ARE EXPECTED TO LARGELY PREVAIL THIS MORNING AT EYW  
AND MTH, THOUGH A CHANCE OF OCCASIONAL PASSING SHOWERS AND  
THUNDERSTORMS WILL PROVIDE AN OPPORTUNITY FOR PERIODS OF SUB-VFR  
CONDITIONS. THUS, VCSH IS INCLUDED THROUGH 18Z FOR NOW, BUT TIMING  
AND PLACEMENT OF SHOWER ACTIVITY IS UNCERTAIN DUE TO THEIR BEING  
DRIVEN BY BOUNDARIES AND OTHER LOCALIZED TRIGGERS. FOR THIS REASON,  
MENTION OF MORE SPECIFIC IMPACTS AND CATEGORICAL CHANGES WILL BE  
HANDLED BY FUTURE UPDATES AND AMENDMENTS. WINDS WILL GENERALLY BE  
FROM THE SOUTH TO SOUTHWEST AT 5 TO 10 KNOTS.  
 
 
   
CLIMATE  
 
ON THIS DAY IN 1919, A CATEGORY 4 HURRICANE MOVED WEST-NORTHWEST  
THROUGH THE STRAITS. IT PASSED JUST SOUTH OF THE KEY WEST, WHICH  
RECORDED A MINIMUM PRESSURE OF 28.81" (976 MB), A DAILY-RECORD 5.61"  
OF RAIN (ALONG WITH ANOTHER DAILY-RECORD 7.47" OF RAIN ON THE 10TH),  
AND THE ANEMOMETER CUPS BLEW AWAY AT 80 MPH. TROPICAL STORM FORCE  
WINDS LASTED MORE THAN 38 HOURS. AT SAND KEY A MINIMUM PRESSURE OF  
28.35" (960 MB) WAS RECORDED, AND THE ANEMOMETER CUPS BLEW AWAY AT  
84 MPH WIND, AFTER WHICH A PEAK WIND OF 110 MPH WAS ESTIMATED. AT  
THE DRY TORTUGAS THE MINIMUM PRESSURE WAS 27.51" (932 MB), AND A  
SHIP NEAR THE DRY TORTUGAS RECORDED A MINIMUM PRESSURE OF 27.36"  
(927 MB). MANY HOMES WERE UNROOFED, 10 SHIPS WERE LOST, AND ABOUT  
500 PEOPLE WERE KILLED.  
 
 
   
KEY WATCHES/WARNINGS/ADVISORIES  
 
FL...NONE.  
GM...NONE.  
 
 
 
 
 
PUBLIC/MARINE/FIRE...11  
AVIATION/NOWCASTS....MC  
DATA ACQUISITION.....MC  
 
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.
The Nexlab FL Page
Main Text Page