Area Forecast Discussion
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000
FXUS62 KKEY 170853
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
353 AM EST Tue Jan 17 2017

.DISCUSSION...
Isolated showers are moving west/northwestward through the
Straits well south of the Marquesas Keys and Dry Tortugas. Much
lighter and more widely spaced echoes on KBYX doppler radar are
near the Middle and Lower Keys and adjacent waters. Winds remain
moderate to fresh across the Keys service area, with the strongest
breezes in the proximity of the stronger showers well south of the
Dry Tortugas, per the latest available ASCAT pass.

A mid to upper level ridge across the southeastern Gulf of Mexico
and Southern Florida will weaken slowly over the next couple of
days. At the surface, a broad area of high pressure is currently
centered near the mid-Atlantic coast. This high pressure will
settle southward over the next couple of days, with an extension
across South Florida and the Keys into the weekend. Despite a
weakening veered profile, moisture diminishes aloft and the local
airmass remains quite stable. After isolated showers expected
through at least the early portion of this morning, have kept a
dry forecast through Thursday, and then extended it further into
at least Saturday. A slight chance of measurable precipitation
returns Saturday night through Sunday as moderating southerly
breezes extend through the lowest 5000 feet tapping deeper
moisture. Also raised our chance of precipitation for Sunday night
and Monday as a cold front is expected to sweep through the Keys
and surrounding waters. Pegged that POP at 30 percent on this
forecast for those periods, and would not be surprised if this
needs to be bumped even higher on subsequent forecasts. A few
thunderstorms are also expected during the transition of that
front with more unstable conditions in place. A slight chance of
showers remains on the back side of that front...Monday. Up until
that front, expect temperatures to remain 4 to 6 degrees above the
seasonal average.

&&

.MARINE...
Will allow the small craft advisory for the Straits to expire on
this forecast issuance. There may be brief exaggerated winds,
especially south and southwest of the Lower Keys early this
morning in the vicinity of the few stronger showers, but the trend
is downward for the wind speeds. Small craft will need to exercise
caution though in those waters today though. Winds will continue
to diminish through the middle and late days of the work week as
high pressure slides southward across South Florida and the Keys.
Finally a period of more agreeable recreational boating for the
waters surrounding the Florida Keys, especially Wednesday through
Saturday.

&&

.AVIATION...
Mostly VFR conditions will prevail at both the Key West and Marathon
International terminals through at least 18/12z. Mainly east winds
will also prevail around 10 knots, with higher gusts if episodic
showers pass nearby. Timing of showers will be problematic and
amendments will be issued in response to impending events.

&&

.CLIMATE...
On this date in Florida Keys weather history, in 2011. 1.91 inches
of rain fell at the Key West International Airport. This set the
daily record for rainfall in Key West on January 17th. Rainfall
records for Key West date back to 1871.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  81  71  82  71 / 10 -  -  -
Marathon  84  71  82  71 / 10 -  -  -

&&

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

&&

$$

Public/Marine/Fire...04
Aviation/Nowcasts....BWC
Data Collection......DR

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