Area Forecast Discussion
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FXUS62 KKEY 251846

Area Forecast Discussion
National Weather Service Key West FL
246 PM EDT Sat Mar 25 2017

.DISCUSSION...In the middle to upper level(700-200 mb), latest
available model streamline analysis overlaid on top of satelitte
imagery as of 200 pm, depict a well defined cold core cyclone
over Central Missouri. This system separates a strong northern and
southern stream jet, with a 75 to 100 knot jet at 250 mb rounding
the base of this system across the North Central Gulf of Mexico,
then arcing northeastwards to North Carolina. Downstream of that,
the axis of a regional scale warm middle and upper ridge pokes
northeastward to near 34 North 73 West from Western Cuba. And east
of that, there is a well defined middle and upper level trough
with its axis from near 32 North 68 West southwest to near the
Windward Passage.

At the surface and in the lower to middle levels(Surface to 700
mb), Latest satelitte imagery overlaid with marine and land
surface observations and analysis as of 200 pm, details the
center of a 1030 mb anticyclone is near 34 North and 65 West with
the western periphery of this surface ridge across South Carolina.
The Florida Keys are beneath the southwestern periphery of this
ridging, with moderate to fresh east winds continuing to blow
across the islands and surrounding waters this afternoon.

.CURRENTLY...As of 200 pm, skies are mostly sunny across the
islands and adjoining waters. Temperatures across the islands are
in the lower 80s with dewpoints in the middle 60s. Key West and
Miami radars do not detects any echoes attm. C-man stations along
the Florida Reef are registering east winds at 15 to 20 knots and
gusty, near 15 knots in Florida Bay and at Smith Shoal Light.

.SHORT TERM...Tonight thru Monday Night, A fairly typical benign
weather pattern is in store for us as we finish the last week of
March. Stronger ridging out over the West Central Atlantic
extending into the Southeastern United States will gradually
weaken tonight through Monday Night. The aforementioned middle and
upper trough now located north of Hispaniola in combination with
a stalling frontal boundary will allow for development of a gale
center/strong non tropical low tonight through Sunday night, then
moving about 500 nm north of Puerto Rico by Monday Night. As a
result, moderate to fresh breezes again tonight, will slacken to
gentle to moderate breezes Sunday thru Monday Night, given the
loosening of the MSLP gradient. After a very slight chance of
showers again tonight, any chance for remain has been removed from
the grids thereafter. Highs in the lower to middle 80s with lows
near 70.


.LONG TERM...Tuesday thru Saturday, A weak broad high is progged
to set up over the Florida Peninsula during Tuesday and Tuesday
night. The system strengthens only slightly for Wednesday through
late in the week. Little moisture is available for the chance for
rain for Tuesday through Thursday Night, with highs in the mid 80s
and lows near 70. Another system is progged to move through the
Tennessee Valley for Friday thru the weekend, which will increase
local winds given convergence and increase lower to middle level
moisture. For now just have isolated showers, a dime pop for just
showers attm for Friday thru Saturday, but a cold middle level
system also in tandem with this low at 500 mb at this particular
track usually introduces sufficient dynamics for at least
isolated thunderstorms given chilling of mid levels and associated
instability. Will wait and see if these indications continue.
High in the mid 80s and lows in the lower to mid 70s.


.MARINE...SCA will continue across the Florida Straits thru the
evening, with SCEC conditions across the rest of the waters,
except maybe Florida Bay and nearshore waters north of the Middle
and Lower Keys. Winds and Seas should be below headline or
advisory criteria for Sunday through Thursday Night.


.AVIATION...VFR conditions will prevail at the island terminals tonight. Surface
winds will be out of the east at 10 to 15 knots and gusty, relaxing
later in the afternoon and evening.


Key West  73  83  72  83 / 10 -  -  -
Marathon  72  83  71  84 / 10 -  -  -


GM...Small Craft Advisory thru this evening for GMZ052>055-



Data Collection......Vickery

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