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fxus62 kmfl 210519 

Area forecast discussion
National Weather Service Miami Florida
1219 am EST Tue Feb 21 2017

Aviation...patchy fog possible over the interior through
daybreak, with local MVFR cigs affecting kapf through around 09z
before moving offshore. Otherwise, dry and prevailing VFR through
taf cycle.East-northeast flow 4-7kts at most sites through remainder of
night, though a few may decouple and become calm. East-southeast winds pick
up to 9-12kts after 15z, with Gulf Breeze brings winds around to
the SW after 20z at kapf.


Previous discussion... /issued 308 PM EST Mon Feb 20 2017/

Discussion...quiet weather over South Florida today, due to a
ridge at 500mb over the area, and a surface high, centered well to
the north. This will continue tomorrow, with the ridge and sfc
high slowly sliding east, ahead of a strong system, currently over
the plains, nearing the Mississippi River valley.

This system will bring our next opportunity for active weather for
the middle of the week. Both the GFS and the European model (ecmwf) have a 500mb
cutoff low dropping down, pinching off from the main flow Tuesday
night, centered near New Orleans late Wednesday evening. The low
moves into the eastern Gulf of Mexico Wednesday morning. This will
push moisture and instability into the region early Wednesday
morning. Pops begin showing up in the forecast between 06z and 12z
Wednesday, with a chance of showers along both coasts, and a
slight chance in much of the interior, mainly due to some
isentropic lift ahead of the system.

By mid day Wednesday, a cold front takes better shape, bringing
the threat show thunderstorms to South Florida, mainly from
Wednesday afternoon into late Wednesday evening. There is a
35-45kt low level jet Wednesday afternoon and evening as well,
mainly affecting the southern portion of South Florida. This may
help to amplify any storms that do develop. The models are
showing the front to be off the Atlantic coast by 12z Thursday
morning. The actual surface low is currently progged to pass
across the Florida Peninsula Thursday morning, somewhere over
central Florida. Models are indicating there may be some wrap
around showers that may affect the County Warning Area on Thursday, mainly in the
morning hours.

Given there is no significant cold air mass, the highs will be
slightly cooler on Wednesday and Thursday, probably do to cloud
cover, not cold advection. By Friday, highs will be back into the
mid 80's across the region.

For the end of the week, and the weekend, models are showing a
return to mostly quiet weather for South Florida.

Marine...marine conditions for the next week will be relatively
quiet, with the exception of Wednesday and Thursday, when a low
pressure system bring the threat of showers and thunderstorms to
the region. The seas are forecast to build slightly for the middle
of the week, currently to around 4 feet in the Gulf Stream, then
subside some by the weekend.

The easterly wind today and tomorrow will place a moderate risk
of rip currents in the forecast for Tuesday along the East Coast.
The wind is forecast to turn more southeasterly, and increase on
Wednesday, which may increase the threat of rip currents to high,
especially for Miami Beach. With the frontal passage, and the wind
turning westerly, the threat of rip will diminish quickly
Thursday morning.


Preliminary point temps/pops...
West Palm Beach 80 68 77 65 / 0 20 80 70
Fort Lauderdale 80 70 78 65 / 10 30 70 70
Miami 80 69 80 66 / 10 30 70 70
Naples 81 66 73 61 / 0 20 80 40


Mfl watches/warnings/advisories...

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