Area Forecast Discussion
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FXUS62 KKEY 261259

Area Forecast Discussion
National Weather Service Key West FL
859 AM EDT MON SEP 26 2016

The satellite viewpoint shows a mid to upper level low over the
Florida Big Bend area. South of this low we find very good upper
level diffluence over South Florida and the Keys area this morning.
precipitable moisture in the morning sounding is about average, but
there is ample lift due to the cyclonic flow aloft, and light winds
at the surface. Winds are generally east to southeast at 5 to 10
knots from the marine reporting stations, and variable at 5 knots or
less at the island terminals.

The diffluence aloft and light winds in the lower levels with
enhance ventilation above any convective cells that move through the
area today. Will keep likely showers and thunderstorms today and
continue the high end chance of showers and thunderstorms overnight
and Tuesday. These showers and thunderstorms will not move much due
to weak steering flow, the mean wind from the LFC to the EL is
around 10 knots, so any showers that develop will likely rain out
nearly in place. The addition of solar insolation will enhance
development, but with the amount of cirrus cloud cover expect that
this will be minimal. The mid level portion of the low over North
Florida will gradually break down into a trough through tonight. The
evacuation aloft will remain through the fruition of this process.
Thereafter, weak high pressure will take control over the area late
Tuesday through Thursday night. Will keep a chance of showers and
slight chance of thunderstorms in through Sunday due to more typical
wet season environment.


No advisory or cautionary statements are expected. Weak high pressure
will remain over the Keys Area through Saturday. Expect higher seas
and gusty winds in and near numerous showers and thunderstorms today
through Tuesday. Winds will remain light to occasionally gentle
through the forecast.


A weak and wet pattern will keep the threat of showers and at least
a few thunderstorms in the outlook for the KEYW and KMTH terminals.
Have a VCTS at both locations in the near term based on the latest
loop of a nearby available doppler radar. Due to the slow-moving
nature of the storms, will amend as storms near the terminals or
develop nearby...but expect at least a few periods of MVFR of even
brief IFR conditions at both location...just as been the case over
the past few days.


September 26th, on this date in Key West climate history,
in 2011, the daily record rainfall of 3.36" was recorded. Rainfall
records date back to 1871.


.KEY Watches/Warnings/Advisories...


Data Collection......Chesser

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