Area Forecast Discussion
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000
FXUS62 KKEY 240845
AFDKEY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KEY WEST FL
445 AM EDT SUN MAY 24 2015

.DISCUSSION...AN UPPER LEVEL RIDGE EXTENDS NORTHWARD FROM THE WESTERN
CARIBBEAN INTO THE EASTERN UNITED STATES. AS A RESULT...A DEEP LOW-
MID TROPOSPHERIC ANTICYCLONIC CIRCULATION HAS DEVELOPED ACROSS THE
WESTERN NORTH ATLANTIC. A SURGE OF EASTERLY BREEZES SWEPT THROUGH
THE FLORIDA KEYS LAST EVENING...RESPONDING TO THE DEVELOPING SURFACE
HIGH PRESSURE SYSTEM. CURRENT MARINE OBSERVATIONS INDICATE SUSTAINED
WINDS IN THE HIGH TEENS (KTS) WITH FREQUENT GUSTS INTO THE LOWER 20S.
SHOWER COVERAGE HAS LESSENED WITHIN THE PAST FEW HOURS DUE TO MID
LEVEL SUBSIDENCE...SUPPORTED BY RECENT SATELLITE BASED FORECAST
SOUNDINGS.

.SHORT TERM (TODAY THROUGH TUESDAY)...FORECAST REASONING HAS NOT
CHANGED...FRESH EASTERLY BREEZES WILL PERSIST THROUGH THE SHORT TERM.
RAIN CHANCES WILL BE GOVERNED BY THE WEAK CONVERGENT SWATHS AHEAD OF
UNDULATING WIND SURGES. SUBSIDENCE SURROUNDING 700 MB WILL LIMIT DEEP
CONVECTION. HOWEVER...GIVEN THE DEEP EASTERLY FLOW (REACHING 400 MB
BY TUESDAY)...PARCELS MAY BE ABLE TO ESCAPE INTO LEVELS OF FREE
CONVECTION. THEREFORE...WE HAVE RETAINED A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS. AN IDENTIFIABLE SWATH (MIMIC TPW) OF INCREASED
MOISTURE WILL REACH THE FLORIDA KEYS SOMETIME MONDAY. RAIN CHANCES
MAY NEED TO BE NUDGED UPWARD AS THIS FEATURE APPROACHES. HIGH
TEMPERATURES WILL REACH INTO THE UPPER 80S...AND LOWS WILL STRUGGLE
TO FALL THROUGH THE LOWER 80S.

&&

.LONG TERM (TUESDAY NIGHT THROUGH SATURDAY)...UNDULATING EASTERLIES
WILL CONTINUE THROUGH THE LONG TERM....RESULTING IN BREEZY
EASTERLIES AND SLIGHT RAIN CHANCES. NO CHANGES NEEDED FOR THE
FORECAST.

&&

.MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE STRAITS OF
FLORIDA...AND ADVISORIES WILL LIKELY BE HOISTED TONIGHT FOR THE
REMAINING COASTAL WATERS. WINDS WILL PEAK AND LULL FOR THE NEXT
SEVERAL DAYS. THE STRONGEST BREEZES WILL FILTER INTO THE KEYS COASTAL
WATERS MONDAY NIGHT. SEAS AS HIGH AS 8 FEET WILL BE POSSIBLE EARLY
TUESDAY MORNING IN THE GULF STREAM. FROM SYNOPSIS...AN ATLANTIC RIDGE
OF HIGH PRESSURE WILL EXTEND ACROSS THE CAROLINAS TODAY THROUGH
THURSDAY. FRESH EASTERLY BREEZES WILL PREVAIL ACROSS ALL KEYS COASTAL
WATERS THROUGH THE FORECAST PERIOD.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL AT THE ISLAND TERMINALS
TODAY. SURFACE WINDS WILL BE OUT OF THE EAST AT 10 TO 15 KNOTS...WITH
FREQUENT GUSTS NEAR 20 KNOTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST  87  79  87  79 / 20 20 20 20
MARATHON  89  79  89  79 / 20 20 20 20

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
     GMZ052>055-072>075.

&&

$$

PUBLIC/MARINE.........CLR
AVIATION/NOWCASTS.....11
DATA COLLECTION.......VICKERY

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