000
FXUS62 KKEY 301427
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
1030 AM EDT THU OCT 30 2008

.DISCUSSION...
CURRENTLY - A BROAD ~1032 MB HIGH CENTERED OVER GEORGIA...IN
COMBINATION WITH PERSISTENT LOWER PRESSURES IN THE WESTERN CARIBBEAN
HAS QUICKENED THE FLOW ACROSS THE KEYS AREA THIS MORNING. CMANS HAVE
BEEN REPORTING NORTH TO NORTHEAST WINDS OF 15 TO 20 KNOTS...AND
ISLAND LOCATIONS ARE MOSTLY NEAR 15 MPH. NORTHEAST FLOW IN THE
LOWER TROPOSPHERE...UNDERNEATH A SHARP SUBSIDENT INVERSION HAS
CONTRIBUTED TO LOTS OF STRATOCU ACROSS KEYS WATERS OUTSIDE OF THE
SOUTH FLORIDA SHADOW. ALOFT...A STUBBORN SWATH OF CIRRUS EMBEDDED
WITHIN THE SOUTHERN FLANK OF THE SUBTROPICAL JET...CONTINUES TO
STREAM EASTWARD ACROSS AND JUST NORTH OF OUR AREA. TEMPERATURES NOW
CLIMBING UP THROUGH 70 DEGREES ARE MUCH MILDER THIS MORNING THAN
YESTERDAY...WHILE DEW POINT TEMPERATURES HAVE EKED UPWARDS INTO THE
UPPER 50S. A STILL RELATIVELY DRY AIRMASS HAS KEPT SHOWER

SHORT TERM UPDATE (THIS AFTERNOON) - THE PREVIOUSLY MENTIONED HIGH
PRESSURE SYSTEM WILL CONTINUE TO MEANDER OVER THE SOUTHEASTERN
STATES AND STRENGTHEN UNDER THE INFLUENCE OF MID AND UPPER LEVEL
RIDGING. OUR LOCAL PRESSURE GRADIENT WILL BE ON A TIGHTENING TREND
OVER THE NEXT 24 HOURS. WINDS ARE EXPECTED TO REMAIN NORTH TO
NORTHEAST AND PICK UP A BIT. DAY TIME HEATING OVER SOUTH FLORIDA
SHOULD LIMIT THE AMOUNT OF STRENGTHENING...BUT THE ONGOING
INCREASING TREND APPEARS REASONABLE. WATER TEMPERATURES UPSTREAM OF
THE KEYS HAVE BEEN RUNNING IN THE UPPER 60S TO NEAR 70...THIS ALONG
WITH A COOL AND RELATIVELY DRY AIR MASS SHOULD KEEP DAY TIME HIGHS
IN THE MID 70S. ONGOING FORECAST IS ON TRACK...AND NO UPDATE IS
NECESSARY.

&&

.MARINE...
MARINERS CAN EXPECT WINDS TO GRADUALLY STRENGTHEN THROUGH THE NEXT
24 HOURS AS HIGH PRESSURE BUILDS TO OUR NORTH ALONG WITH LOWER
PRESSURES IN THE WESTERN CARIBBEAN. AN EXERCISE CAUTION IS IN EFFECT
FOR ALL KEYS WATERS. SMALL CRAFT ADVISORIES WILL LIKELY BE REQUIRED
ACROSS ALL KEYS WATERS BY TONIGHT OR TOMORROW...AND THERE IS A
POSSIBILITY THAT A SMALL CRAFT ADVISORY WILL BE REQUIRED FOR THE
ATLANTIC WATERS LATER THIS AFTERNOON OR EVENING.

&&

.AVIATION...
REST OF TODAY...VFR CONDITIONS WILL PREVAIL AT THE ISLAND TERMINALS.
GIVEN A DECENT INVERSION...EXPECT JUST SOME SCATTERED STRATOCU BASES
FOUND BETWEEN 3 AND 5 KFT. EXPECT A STRONG NEAR 1035 MB ANTICYCLONE
TO REASSERT ITSELF ALONG THE MID-ATLANTIC...RESULTING IN SURFACE
WINDS FROM BETWEEN 030 AND 050 DEGREES FROM BETWEEN 12 AND 14 KNOTS
WITH GUSTS BETWEEN 20 AND 25 KNOTS. SO PILOTS CAN EXPECT ABOUT A 45
DEGREE CROSSWIND AT BOTH ISLAND TERMINALS.

&&

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

$$

11/DAF/DR

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