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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
250 PM EDT WED SEP 2 2015

.DISCUSSION...
.CURRENTLY...
SKIES ARE PARTLY TO MOSTLY SUNNY WITH TEMPERATURES HOVERING AROUND 
90 DEGREES ALONG MOST OF THE ISLAND CHAIN. MEANWHILE...LOCAL RADARS 
ARE DETECTING A BAND OF SHOWERS WITH A FEW THUNDERSTORMS ON THE 
NORTHERN TIP OF THE WESTERNMOST LOWER KEYS...BETWEEN SUMMERLAND 
KEY AND KEY WEST. SURFACE WISE...A BROAD RIDGE IS DRAPED ACROSS 
THE FLORIDA PENINSULA AND NEAR OUR ENTIRE MARINE 
DISTRICT...RESULTING IN GENERALLY VARIABLE WINDS OF LESS THAN 
10 KNOTS...EXCEPT MOSTLY EAST NEAR 10 KNOTS ON THE OUTER 
FLORIDA STRAITS. 

.SHORT TERM (TONIGHT THROUGH SUNDAY)...
A DEEP LAYERED RIDGE OVER THE SUNSHINE STATE AND THE ADJACENT 
ATLANTIC AND GULF WATERS WILL SLOWLY SPLINTER BEGINNING 
FRIDAY...AS A LENGTHY TROUGH DIGS EQUATORWARD DOWN THE 
FLORIDA PENINSULA AND INTO OUR REGION THIS WEEKEND. BECAUSE OF THESE 
CHANGES ALOFT...LARGE SCALE DESCENT WILL SHIFT TO UPWARD 
LIFT BUT TO WHAT EXTENT REMAINS UNCERTAIN. BUT UNTIL 
THEN...MESOSCALE FORCING PRIMARILY IN THE FORM OF CLOUD LINE 
GENESIS WILL BE THE MAIN PRECIPITATION SOURCE FOR THIS 
AFTERNOON THROUGH AT LEAST FRIDAY EVENING. WITH THAT SAID...WILL 
MAINTAIN CHANCE 30 TO 40 PERCENT 12 HOUR POPS WHICH IS A BLEND OF 
THE ECE/MEX MOS GUIDANCE. 
 
&&

.LONG TERM (SUNDAY NIGHT THROUGH WEDNESDAY)...
THE UNUSUALLY DEEP LARGE SCALE CYCLONIC FLOW COVERING OUR REGION 
WILL GRADUALLY TRANSITION TO DEEP ANTICYCLONIC...AS THE SUBTROPICAL 
RIDGE EXPANDS WESTWARD BY TUESDAY THROUGH AT LEAST WEDNESDAY. GIVEN 
PLENTY OF MOISTURE WITHIN SYNOPTIC SCALE ASCENT...WILL RETAIN 40 
PERCENT POPS THROUGH MONDAY NIGHT AND LOW CHANCE POPS THEREAFTER. 
PLENTY OF STRONG INSOLATION WILL ALLOW HIGH TEMPERATURES TO CLIMB 
NEAR 90 DEGREES WITH OVERNIGHT LOWS NEAR 80. 

&&

.MARINE...
OUTSIDE OF SHOWERS...THUNDERSTORMS AND POSSIBLE WATERSPOUTS...LIGHT 
TO GENTLE WINDS WILL PREDOMINATE ON OUR MARINE DISTRICT FOR THE 
BALANCE OF THIS WEEK...WITH A SLIGHT INCREASE ESPECIALLY ON THE 
WATERS ADJACENT TO THE UPPER KEYS THIS WEEKEND. 

&&

.AVIATION...
THE BEST CHANCE FOR A SUB VFR ENCOUNTER WILL BE FOR THE BALANCE 
OF THIS AFTERNOON AND EARLY THIS EVENING...OTHERWISE...VFR 
CONDITIONS WILL PREVAIL AT THE KEY WEST AND MARATHON TERMINALS. 
WINDS WILL BE GENERALLY VARIABLE AT LESS THAN 10 KNOTS. 
  
&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  83  90  82  91 / 20 30 30 30 
MARATHON  82  92  82  93 / 20 30 30 30 

&&

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

$$

PUBLIC/MARINE.........APA
AVIATION/NOWCASTS.....KN
DATA COLLECTION.......SC/BF

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