Area Forecast Discussion
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FXUS62 KKEY 271901

Area Forecast Discussion
National Weather Service Key West FL
301 PM EDT Sat May 27 2017

Persistent cumulus cloud lines have been anchored onto the lower and
middle Florida Keys today, with a recent shower developing over
central Big Pine Key. A mainland seabreeze has developed turning
winds southerly across the middle and upper Keys, with a light
northerly flow in part to a strong portion of the ridge
maintaining itself across the eastern Gulf of Mexico.

Tonight through Tuesday, the ridge is expected to bifurcate
Sunday and Monday afternoons in part to heating of the Florida
Peninsula, thus light and variable winds are likely to continue.
Deep mid- level ridging across the eastern Gulf and Florida will
shove recognizable lower tropospheric moisture convergence well
south of the Keys, with moisture depth oscillating between 900 and
850 mb. The surface ridge strengthens slightly Monday night,
increasing east to southeast winds and resulting in gradual
increase in rain chance to 20 percent by Tuesday.

Tuesday night through Wednesday night, gradual strengthening of
the ridge to the north of the Keys will result in freshening east
to southeast breezes and enough moisture flux for slight chances
of showers as moisture depth increases to near 800 mb.

Thursday through Saturday, lower tropospheric ridging slides into
the western Atlantic leaving the Keys in a moderately deep
east-southeast flow, albeit with a mean near 10 knots. Low to mid
level lapse rates remain near 6.0C, with anticyclonically curved
jet segment a ways to the north. It is possible an introduction
of a slight chance of thunder may be needed late next week.


Light southerly seabreezes across Florida Bay and light northeast
winds becoming northerly less than 10 knots near the Lower Keys can
be expected through Sunday evening, with a light and steady
northeast to wind 5 to 10 knots over the open Straits. High
pressure strengthening north of the Keys by mid-week will freshen
east to southeast winds, with perhaps some small craft caution
headlines for the Straits by Tuesday night.


Clouds aligned along portions of the Middle and Lower Keys may
produce sub-VFR conditions at the KEYW and KMTH terminals through
late afternoon. That possibility has been tempoed at both locations.
Otherwise, expect VFR conditions through most of tonight with light
breezes, variable at times.


On this date in 1984, 2.95 inches of rain was measured in Key West.
This set the daily rainfall record for May 27th in the city.
Rainfall records for Key West date back to 1871.


Key West  81  89  82  89 / -  -  -  10
Marathon  82  92  82  92 / -  -  -  10




Data Collection......Chesser

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