Area Forecast Discussion
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FXUS62 KKEY 241910

Area Forecast Discussion
National Weather Service Key West FL
310 PM EDT Sat Mar 24 2018

High pressure is centered just east of Central Florida and
continues to support moderate east breezes across the Florida
Keys. Temperatures are a little warmer today and have reached the
upper 70s in most locations. Humidity is comfortable for Keys
standards, with dewpoints remaining in the upper 50s. Its hard to
have dewpoints below 60 with winds south of east. Skies are mostly
sunny and the KBYX radar is echo free.

.SHORT TERM (Tonight through Tuesday)...
A short wave trough apparent on water vapor imagery will dive
southeast into the Ohio River Valley tonight, then exit the
Eastern Seaboard by Sunday evening. In its wake, mid-upper level
ridging centered in Central America will amplify across the
Eastern United States. A formidable anticyclone will develop
downstream from the ridging aloft, then spread southward through
the extreme western North Atlantic. Rain chances are nil until
Monday night, when the gradient from the anticyclone forces a low
level mass surge through the island chain. Meager low level
moisture will peak within the convergence ahead of the wind surge.
This will be late Monday night or early Tuesday, so we introduced
10% chances for both periods. Through the short term,
temperatures will trend warmer, except for Sunday night. A brief
episode of radiational cooling will drop temperatures to 65
degrees, favoring the larger islands.


.LONG TERM (Tuesday night through Saturday)...
Breezy easterlies will persist Tuesday night through Wednesday,
then turn to the southeast Wednesday night through Thursday night.
Temperatures will warm into the lower 80s/mid 70s as winds turn
to the southeast. A lost cold front will challenge climatology
Friday through Saturday. Current ensemble solutions have this
surface trough dying very near the Keys. To account for the
stalled front, we introduced rain chances Friday night and
Saturday. No other changes needed.


Small Craft Should Exercise Caution across the Straits of Florida
due to east winds 15 to 20 knots and seas as high as 6 feet. An
area of high pressure centered over North Florida will slide
eastward into the western North Atlantic tonight. A lengthy ridge
will build southwest down the Eastern United States Sunday through
Tuesday. Strong northeast to east breezes are expected Tuesday
and Tuesday night. Thereafter, breezes will slowly veer to the
southeast and diminish as high pressure slides eastward into the
western North Atlantic.


VFR conditions will prevail at the EYW and MTH terminals tonight and
on Sunday. East winds 10 to 15 knots will decrease tonight to
5 to 10 knots and become from the southeast.


Key West  69  81  69  81 / 0 0 -  -
Marathon  70  82  69  83 / 0 0 -  -




Data Collection......DR

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