Area Forecast Discussion
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FXUS62 KKEY 270146

Area Forecast Discussion
National Weather Service Key West FL
946 PM EDT Mon Jun 26 2017

.DISCUSSION...In the middle and upper levels(700-200 mb), latest
available satelitte imagery overlaid with model streamline
analysis as of 800 pm depicts a prominent cold core middle and
upper trough situated across the Eastern two-thirds of the United
States. The base of the trough reaches down to along the Central
and Eastern Gulf Coast. South of that feature, a regional scale
middle and upper ridge is centered near 27 N 76 W, with the axis
across South Florida.

At the surface and in the lower to middle levels(Surface to 700
mb), latest marine and land observations and analysis as of 800 pm
detail that a stationary frontal boundary has reached as far south
as Northern Florida. South of that a weak surface ridge is
indicated from the West Central Tropical Atlantic Ocean west
southwest to across South Florida. The 00Z sounding at Key West
illustrated a gentle mostly east from the surface to up to 500 mb,
with typically moderate amounts of moisture with columnar PWAT at
1.67, only .01 inches less than 24 hours prior.

.CURRENTLY...As of 800 pm, skies are mostly clear across the
islands and surrounding waters, with only a few tiny boundaries
across GMZ033 attm and false echoes elsewhere. Temperatures across
the islands are generally in the middle 80s with dewpoints in the
middle to upper 70s. C-man stations along the Florida Reef are
registering east to southeast at 5 to 10 knots, and island
platforms are east to southeast at 5 to 10 mph.

.SHORT TERM...Overnight, indications remain consistent of a weaker
pressure pattern with a locally bifurcated surface pressure
pattern on either side of the South Florida Peninsula tonight and
tomorrow. ECMWF and GFS Forecast soundings tonight thru 12Z
illustrate decent middle level drier air above the area overnight.
This combined with a weaker 0-6 km average wind will be
prohibitive shower development across the area and surrounding
waters. But nevertheless, boundary collisions and PWAT around 1.75
inches still supports isolated shower/thunderstorms. So made and
update to lower rain chance back into this category. No other
changes on this cycle. Decent moisture will remain in the column
on Monday, with mixed signals for mesoscale cloud line shower
development, but given strong insolation and light winds, will
maintain low chances for showers during Tuesday.


.MARINE...No watches, warnings, or advisories are in effect. A
Bermuda High will govern the weather pattern across the Florida
Keys and adjacent coastal waters from tonight through Saturday.


.AVIATION...Overnight, VFR conditions will prevail at both the
KEYW & KMTH Int`l island terminals. Winds will be mostly from the
east aoa 5 to 8 knots and just some scattered cumuli with bases
aoa FL020.


On this date in Keys Weather History, 1952, a high temperature of
93 degrees was recorded in Key West. This set the daily record
for warmest temperature in Key West for June 26th, a record which
still stands 65 years later. Temperature records for Key West
date back to 1872.




Upper Air/Data Collection......L. Kasper

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