796  
FXUS62 KKEY 230829  
AFDKEY  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE KEY WEST FL  
429 AM EDT SAT OCT 23 2021  
   
DISCUSSION
 
 
OVERNIGHT, RAINFALL COVERAGE ACROSS THE CWA HAS BEEN SOMEWHAT  
LOWER THAN INITIALLY ANTICIPATED EARLIER THIS EVENING. THIS IS  
LIKELY A PRODUCT OF COLLAPSING LOW-LEVEL WINDS, WEAKLY DIFFLUENT  
FLOW, AND THE TROPOSPHERIC VERTICAL PROFILE BEING CONVECTIVELY  
WORKED OVER AT MOST LOCATIONS THROUGHOUT THE DAY ON FRIDAY. CIMSS  
SATELLITE- DERIVED VORTICITY PRODUCT HIGHLIGHTS QUASISTATIONARY  
CYCLONIC FLOW ACROSS THE STRAITS OF FLORIDA AND CUBA. MIMIC TOTAL  
PRECIPITABLE WATER PRODUCT HIGHLIGHTS A SIGNIFICANT MOISTURE  
GRADIENT ACROSS SOUTH FLORIDA, WITH DRY AIR TO THE NORTH AND  
SUBSTANTIAL MOISTURE TO THE SOUTH, INCLUDING IN THE VICINITY OF  
THE FLORIDA KEYS. SKIES ARE PARTLY TO MOSTLY CLOUDY ACROSS THE  
ISLAND CHAIN, WITH TEMPERATURES IN THE MID TO UPPER 70S.  
 
ALTHOUGH FORECAST SOUNDINGS CONTINUE TO SHOW ONLY MODEST  
INHIBITION AND SUBSTANTIAL MOISTURE, THERE WILL ONLY BE WEAK  
LARGE-SCALE FORCING FOR ASCENT FOR THE REMAINDER OF THE WEEKEND.  
COMBINED WITH THE WEAK STEERING FLOW, HAVE ELECTED TO NUDGE POPS  
DOWNWARD, ALTHOUGH CONFIDENCE IN THIS SHORT-TERM FORECAST IS  
SOMEWHAT LOWER THAN NORMAL. WITH VERY WEAK LOW LEVEL NORTHEAST TO  
EAST FLOW, A CUMULUS CLOUD LINE CAN ALSO NOT BE RULED OUT IN THE  
VICINITY OF THE LOWER AND MIDDLE KEYS THIS AFTERNOON, ALTHOUGH  
THERE REMAINS A QUESTION OF WHETHER THERE WILL BE SUFFICIENT SOLAR  
INSOLATION FOR THIS TO OCCUR. ALL IN ALL, CONVECTIVE INITIATION  
WILL BE THE MAIN FORECAST CHALLENGE FOR THE NEXT COUPLE OF DAYS.  
 
A STATIONARY FRONT CURRENTLY OVER THE NORTHERN GULF COAST WILL  
EVENTUALLY PUSH SOUTHEASTWARD EARLY NEXT WEEK BEFORE DECAYING OVER  
SOUTH FLORIDA. ALTHOUGH TEMPERATURES AND DEW POINTS WILL REMAIN  
UNCHANGED, SUBSTANTIAL MID-LEVEL DRYING IS EXPECTED AS THIS  
BOUNDARY PUSHES THROUGH. THUS, CONTINUING TO ADVERTISE REDUCED  
RAIN CHANCES FOR TUESDAY AND WEDNESDAY.  
 
A POTENT TROUGH APPROACHING THE WEST COAST WILL PUSH EASTWARD  
THROUGHOUT THE WORK WEEK, REACHING THE FLORIDA PENINSULA BY  
THURSDAY. THIS FEATURE WILL BE MONITORED THROUGHOUT THE WEEK FOR  
POSSIBLE INCREASED RAIN AND THUNDER AS IT APPROACHES THE CWA.  
ALTHOUGH DETAILS WILL BE IRONED OUT IN OTHER FORECAST CYCLES, VERY  
COMFORTABLE DEWPOINTS AND PERHAPS COOLER CONDITIONS MAY TRAIL  
THIS FRONTAL FEATURE. STAY TUNED.  
 

 
   
MARINE
 
 
NO WATCHES, WARNINGS, OR ADVISORIES ARE IN EFFECT FOR THE FLORIDA  
KEYS COASTAL WATERS. FROM SYNOPSIS, A WEAK, BROAD DOME OF HIGH  
PRESSURE WILL REMAIN ENTRENCHED ACROSS THE ATLANTIC, WITH THE  
ASSOCIATED RIDGE AXIS EXTENDING ACROSS CENTRAL FLORIDA. LIGHT TO  
GENTLE NORTHEAST TO EAST BREEZES ARE EXPECTED THROUGH MONDAY. A  
SWATH OF ENHANCED MOISTURE WILL REMAIN OVER THE FLORIDA KEYS  
COASTAL WATERS, RESULTING IN ABOVE NORMAL RAIN CHANCES. A FRONTAL  
BOUNDARY CURRENTLY OVER THE GULF COAST WILL PUSH SOUTHEASTWARD  
EARLY NEXT WEEK, WITH DRIER CONDITIONS ANTICIPATED TUESDAY AND  
WEDNESDAY. A SECOND FRONTAL BOUNDARY WILL APPROACH THE FLORIDA  
PENINSULA ON THURSDAY, RESULTING IN A PERIOD OF ELEVATED RAIN AND  
THUNDER CHANCES.  
 

 
   
AVIATION
 
 
VFR CONDITIONS WILL PREVAIL AT THE ISLAND TERMINALS. THERE WILL BE A  
CHANCE FOR SLOW MOVING SHOWERS AND A FEW THUNDERSTORMS TODAY,  
RESULTING IN SPELLS OF SUB VFR CONDITIONS. THERE IS CONSIDERABLE  
UNCERTAINTY CONCERNING TIMING AND LOCATION OF ANY CONVECTION.  
THEREFORE, EXPLICIT MENTION IS LEFT OUT OF THE TAF'S. SURFACE WINDS  
WILL BE LIGHT OUT OF THE NORTHEAST TO EAST.  
 

 
   
CLIMATE
 
 
IN 2005, A VIOLENT WATERSPOUT PASSED JUST WEST OF KEY WEST IN THE  
OUTERMOST RAINBAND OF APPROACHING HURRICANE WILMA AT AROUND 4 PM.  
 

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

 
 

 
 
PUBLIC/MARINE/FIRE...BT  
AVIATION/NOWCASTS....11  
DATA ACQUISITION.....AP  
 
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