Area Forecast Discussion
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FXUS62 KKEY 171335
AFDKEY

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
934 AM EDT WED SEP 17 2014

.DISCUSSION...
.CURRENTLY...
EARLY VISIBLE SATELLITE PHOTOGRAPHS SHOW MOSTLY SUNNY SKIES WITH
TEMPERATURES SLOWLY REBOUNDING INTO THE LOWER TO MID 80S ALONG THE
ISLAND CHAIN. MEANWHILE...LOCAL RADARS ARE DETECTING A FEW SHOWERS
ON THE FLORIDA STRAITS ALONG WITH A BROKEN BAND OF SHOWERS AND AN
EMBEDDED THUNDERSTORM ON THE OUTER WATERS OF MAINLAND MONROE.
SURFACE WISE...A TROUGH OF LOW PRESSURE IS DRAPED ACROSS NORTH
CENTRAL FLORIDA AND THE ADJACENT ATLANTIC AND GULF WATERS...WITH A
RIDGE AXIS IN OUR COUNTY WARNING AREA. ON OUR MARINE
DISTRICT...C-MAN STATION PLATFORM OBSERVATIONS INDICATE VARIABLE
WINDS OF LESS THAN 5 KNOTS. OTHERWISE...OUR MORNING SOUNDING REVEALS
A TEMPERATURE/DEWPOINT DEPRESSION OF 8 AND 10 DEGREES C AT 850 AND
700 MB RESPECTIVELY...WITH LIGHT AND CHAOTIC WINDS REACHING WELL
INTO THE TROPOSPHERE.

.SHORT TERM (REST OF TODAY)...
A DEEPENING TROUGH OVER THE EXTREME SOUTHEAST UNITED STATES AND
NORTH FLORIDA WILL CONTINUE TO PRESS SOUTHWARD...WITH THE LOW LEVEL
ANTICYCLONE HOLDING NEAR OUR AREA. WITH THE CLOSE PROXIMITY OF THIS
RIDGE...A LIGHT AND CHAOTIC STEERING FLOW WILL DOMINATE OUR SENSIBLE
WEATHER. WITH THAT IN MIND...MESOSCALE INTERACTIONS IN THE FORM OF
CLOUD LINE GENESIS WILL BE THE SOLE SOURCE OF PRECIPITATION. GIVEN A
FEW NARROW LAYERS OF DRY AIR BELOW 700 MB...LOW CHANCE POPS WITH
HIGHS NEAR 90 DEGREES SEEM FINE. SINCE THE CURRENT FORECAST
SITUATION HANDLES THE SITUATION WELL...NO ADJUSTMENTS ARE
PLANNED.

&&

.MARINE...
OUR MORNING RAWINDSONDE DEPICTS NORTHWEST WINDS OF 4 AND 3 KNOTS AT
1 AND 2 THOUSAND FEET RESPECTIVELY WHICH COINCIDE WITH THE KBYX VWP.
WITH A TROUGH OF LOW PRESSURE IN NORTH CENTRAL FLORIDA AND THE
ADJACENT ATLANTIC AND GULF WATERS SAGGING SOUTHWARD...THE NEBULOUS
RIDGE LYING NEAR OUR REGION WILL BE SHOVED INTO THE STRAITS. OUTSIDE
OF ISOLATED SHOWERS...THUNDERSTORMS OR POSSIBLE WATERSPOUTS...LIGHT
AND VARIABLE WINDS CAN BE ANTICIPATED ON ALL KEYS COASTAL WATERS FOR
THE BALANCE OF TODAY.

&&

.AVIATION...
VFR WILL PREVAIL AT BOTH THE KEY WEST AND MARATHON TERMINALS WITH
MOSTLY WEST TO NORTHWEST WINDS AROUND 5 KNOTS. CLOUD STREAMERS MAY
FORM IN THE LEE...SOUTH SIDE OF THE ISLAND CHAIN THIS AFTERNOON DUE
TO WEAK WEST TO NORTHWEST STEERING FLOW. THESE CUMULUS STREAMERS
BASED NEAR 025 MAY RESULT IN TEMPORARY MVFR EPISODES MAINLY AT KEY
WEST.

&&

.CLIMATE...SEPTEMBER 17TH...ON THIS DATE IN FLORIDA KEYS CLIMATE
HISTORY...IN 1985...THE DAILY RECORD LOW TEMPERATURE OF 69F WAS
RECORDED. THIS IS ALSO TIED FOR THE COLDEST TEMPERATURE EVER
RECORDED IN SEPTEMBER. TEMPERATURE RECORDS IN KEY WEST HAVE BEEN
KEPT SINCE 1872.

&&

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

&&

$$

PUBLIC/MARINE/FIRE/CLIMATE/DIGITAL...APA
AVIATION/NOWCASTS....................BWC
DATA ACQUISITION.....................EV

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