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FXUS62 KKEY 201941

Area Forecast Discussion
National Weather Service Key West FL
241 PM EST Mon Nov 20 2017

KBYX Doppler radar shows a few patches of mostly light showers
continuing to advance west/southwestward along and just south of
the Keys island chain. Winds have accelerated in the vicinity and
behind these relatively small areas. Under partly to mostly cloudy
skies, temperatures along the Keys island chain are between 75 and

A weakened front has stalled just to the south of the Keys island
chain. Large high surface pressure currently centered over the
Carolinas will push eastward over the next 36 to 48 hours, taking 
the tightened pressure gradient northeastward away from our area.
Our local winds will steadily veer to the east into early Tuesday
morning, and relax significantly during the day Tuesday while
shifting further to the southeast/south.

The gridded forecast elements have been adjusted only a small
amount, mainly during the middle to late portions of the week. 
The latest GFS and ECMWF have come into better agreement with 
regards to developing area of low pressure in the Gulf. The latest
solutions now pull a more discernible but relatively weak low
across south Florida by Friday, whereas the previous GFS had a
more amorphous swirl lifting much more quickly to the northeast.
Thanks to this most recent agreement, will stick close to the
latest GFS MOS numbers in regards to POPs and temperatures. That
said, this forecast will still focus our best chance for
measurable rain in a window from Thursday through Friday, and 
also limit this time frame for accompanied thunderstorms. 
Lingering light showers are possible early this weekend. But, left
any mention of measurable precipitation out of the forecast for 
Sunday and Monday. We may even feel a drier and somewhat cooler 
surge of air by that time as well. 


Will maintain a small craft advisory for the fresh northeast
breezes initially in place across most waters surrounding the
Florida Keys. However, the wind speed trend will definitely be
downward tonight with light to moderate breezes expected by
Tuesday while turning to the east/southeast. 


Occasional bouts of MVFR ceilings/visibility will be possible this 
afternoon and early evening as a cluster of showers moves west-
southwest down, or very near the island chain. Expect northeasterly 
winds to become easterly tonight, losing wind gusts and dipping to 6-
9 knots overnight.

On this date in Keys Weather History, in 1959, the daily record 
rainfall of 7.71 inches was recorded in Key West. This set the daily 
record for rainfall for November 20th, a record that still stands 58 
years later. Rainfall records for Key West date back to 1871.


GM...Small Craft Advisory GMZ031>035-042>044-052>055-072>075.



Data Collection......DR

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