Area Forecast Discussion
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000
FXUS62 KKEY 170931
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
431 AM EST Wed Jan 17 2018

Coolest weather of this early winter season tonight and Thursday
Windy conditions to overspread our entire county warning area
tonight

.DISCUSSION...
.CURRENTLY...
Under partly cloudy skies and northeast winds of 10 to 15 mph,
temperatures are averaging in the mid 60s along the Florida keys.
Meanwhile, local radars are void of any significant precipitation
echoes. Surface wise, a strong, arctic region of high pressure
(1043 mb) is centered over eastern Oklahoma, with a loosening
pressure gradient evident over most of the Sunshine State. On our
marine district, winds are north to northeast near 15 knots.

&&

.SHORT TERM...(Today through Friday night)
A massive, albeit weakening arctic region of high pressure
centered over the southern Great Plains will build southeastward
and down the spine of the Sunshine state, resulting in no
precipitation, "well below normal" temperatures and windy
conditions tonight into Thursday. Thereafter, the progressive and
eroding western Atlantic ridge will allow modifying temperatures
as winds turn predominately from the northeast by the end of this
week. Until then, a northerly trajectory providing moderate cold
air advection combined with cool nearshore gulf waters and Florida
Bay will likely result in the coolest weather along the island
chain this early winter season. (Low temperatures should drop in
the Upper 40s in the extreme Upper Keys and the lower to mid 50s
in the Lower Keys are likely)

&&

.LONG TERM...(Saturday through Tuesday)
Within a progressive and zonal westerly flow aloft, the
aforementioned high pressure system will slide swiftly into the
western Atlantic Ocean with an extensive ridge axis reaching
across the extreme southeast United States before retreating
southeastward into the Bahamas early next week. With this pattern,
low level moisture along with a decaying stable layer will prompt
isolated 10 to perhaps 20 percent pops but with no significant
rainfall expected. High temperatures will range from the mid 70s
this weekend to near 80 early next week with overnight lows
hovering around 70 degrees.

&&

.MARINE...
Despite a brief and subtle respite in the winds, a significant
wind surge will overspread our entire marine district early this
evening, subsequently a Small Craft Advisory will be required
beginning with the 430 pm marine package. Strong north winds will
prevail tonight and early Thursday morning, before abating
appreciably late Thursday into Friday. Thereafter, Moderate mostly
east winds will kick off this weekend with wind speed uncertainty
increasing on Sunday. Stay tuned.

&&

.AVIATION...
VFR will prevail at EYW & MTH through the terminal forecast period.
NE winds sustained near 10 knots early this morning will become
northerly and increase to near 15 knots after 18z, with gusts
approaching 25 to 30 knots after 18/00z.

&&

.CLIMATE...
In 1983, the daily record low temperature of 53 degrees was last
recorded in Key West. Temperature records have been kept since
1872.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West 72 55 60 58 / - 0 0 0 Marathon 72 53 60 58 / - 0 0 0

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.

&&

$$

Public/Marine/Fire...APA
Aviation/Nowcasts....MCLOVIN

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