Area Forecast Discussion
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FXUS62 KKEY 250809

Area Forecast Discussion
National Weather Service Key West FL
409 AM EDT Thu May 25 2017

Currently - A deep layered trough in place over the eastern United
States and eastern Gulf of Mexico is associated with a surface
trough extending across Florida and the eastern Gulf of Mexico.
The Keys remain in a zone of very moist and confluent low level
southwesterly flow. Surface winds have lulled through the
overnight and are now light to gentle out of the south to
southwest. Shower and thunderstorm activity has also lulled for
much of the over night period. This appears to be ending, with new
vigorous shower development appearing in the Florida Straits and
the extreme southeastern Gulf of Mexico.

Forecast - The lower level trough will gradually lift out
northeast as it rotates around the parent low, centered south of
the great lakes. Until then, overall background flow will remain
confluent and is expected to again accelerate this morning. In
addition, overall deep layered cyclonic flow will continue to
support shower and thunderstorm initiation.

Winds will rapidly trend downwards this afternoon and evening as
the surface trough lifts out to the northeast. This will leave
behind a very moist and at least for a little while a still
confluent, if decelerating flow. Flow aloft will shift towards
more zonal with all upper level support shifting off to the north.
Rain chances will trend downwards tonight into the weekend.
Expect near to slightly above normal temperatures outside of rain
cooled areas.

A fairly flat pressure pattern heading into this weekend will give
way to ridging developing in the more usual location, across the
Florida peninsula, while deep layered ridging builds in through
the mid and upper levels. Thunderstorm chances become slim to none
with rain chance falling to slight. Continued near to slightly
above normal temperatures are expected this weekend into next


Winds have lulled in wake of last nights squally weather. However,
winds are expected to surge once more due to a trough over
Florida and the eastern Gulf of Mexico, and a ridge extending
across Cuba and the western Caribbean. A small craft advisory
remains in effect for all Keys waters, but will likely be taken
down later this morning or early this afternoon. Thereafter,
winds will quickly trend downwards out of the west this afternoon,
becoming light and variable overnight. From this weekend into
next week, winds will gradually firm up a bit out of the east to
southeast as ridging returns across the Florida peninsula.


Southerly crosswind gusts will persist at the EYW and MTH terminals
through the morning. Current satellite and radar imagery indicate
increasing coverage of showers across the Florida Keys and adjacent
coastal waters. Rain chances will persist until the southerly winds
shift to westerly this afternoon. Thus, prepare for temporary
periods of IFR VIS and MVFR CIGS. Convective wind gusts will reach
25 knots.


Key West  85  78  87  78 / 70 50 30 30
Marathon  89  78  90  78 / 70 50 30 30


GM...Small Craft Advisory for all Florida Keys waters




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