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999 
FXUS62 KKEY 161009
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
509 AM EST Mon Jan 16 2017

.CURRENTLY...
Partly cloudy skies cover the island chain this morning under an 
light northeast to east wind flow thanks to persistent ridge 
along the eastern seaboard and down the Florida Peninsula. 
Temperatures across the Florida Keys range in the lower 70s with 
dewpoints steady in the middle 60s. Returns from the KBYX radar 
are scant, with the exception of a few periodic returns well out 
over the Straits of Florida. This is not surprising with limited 
moisture and a moderate inversion sampled just below 800mb from 
the 00z KKEY sounding, keeping any cumuli vertically suppressed.


.DISCUSSION...

Persistent ridging across the southeastern U.S. will control the 
sensible weather elements for the Florida Keys the next couple of
days. Winds will remain easterly with the Keys residing on the
southern flank of the high pressure region, and with limited 
moisture rain chances will be near zero. This will also allow 
temperatures to rise 5 to 10 degrees above normal for mid-January,
with dewpoints nudging in to the upper 60s. 

An area of low pressure currently providing a mix of severe and 
wintry weather over the nations heartland will move to the 
northeast, residing near the Great Lakes region on Tuesday. This 
low pressure area will jump off the coast of New England, rapidly
intensifying, shunting the aforementioned high pressure region 
southward across South Florida and the Bahamas on Wednesday. As a
result, winds are expected to begin to collapse Tuesday night and
early Wednesday across the region, remaining light to gentle 
through weeks end. With the high pressure residing overhead or 
just to our east, can expect the above normal temperatures to
continue and slight rain chances heading in to next weekend.

A quick look ahead to next weekend and early next week, model
guidance is indicating a trough of low pressure entering the 
northwestern Gulf of Mexico by the second half of the weekend,
with a potential cold front approaching the Florida Peninsula and
the Florida Keys late Sunday into Monday. Still 7 days out, so
timing and intensity of any cold front will need to be ironed out
the next several days.

&&

.MARINE...
A persistent ridge of high pressure over the western
Atlantic will remain in place through Tuesday, then begin 
shifting southward Tuesday night and reside near or just east of 
the Florida Keys through weeks end. As a result, expect winds and
seas to decrease markedly across all Florida Keys coastal waters 
Tuesday night and Wednesday.

&&

.AVIATION...
VFR conditions will continue at the KEYW and KMTH terminals today 
and tonight. Winds will be out of the east at or around 10 knots.

&&

.CLIMATE...
On this date back in Key West weather history, in the year 1877,
the daily record high temperature of 90F was observed. This is
also the warmest temperature ever recorded during the month of
January, and in fact, it is the only time the temperature has ever
reached 90F in Key West between the dates of November 18th and
April 4th. The last time temperatures breached the 90 degree
barrier in Key West was back on October 9th 2016, when a high
temperature of 90F was observed. Temperature records in Key West
date back to 1872.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  81  70  82  71 / -  -  -  -  
Marathon  83  71  83  71 / -  -  -  -  

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...Small Craft Advisory until 5 AM EST early this morning for 
     GMZ042>044-052>055-072>075.

&&

$$

Public/Marine/Fire...Fling
Aviation/Nowcasts....04
Data Collection......DR

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