Area Forecast Discussion
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FXUS62 KTAE 140145

845 PM EST Thu Nov 13 2014

.Near Term [Through Tonight]...

Strong low-level CAA continues in the wake of the cold front. As
of 01Z, temperatures in the northwest part of our area have been
trending near the colder end of model guidance which happens to be
comprised of primarily WRF-ARW runs. Therefore, we trended the
forecast with an even blend of the previous forecast and a
consensus of the most recent WRF-ARW runs. This lead to a slightly
expanded area at risk of a freeze tonight, and the Freeze Warning
has been expanded slightly south and east in collaboration with
NWS Atlanta. Wind chills should get into the 20s by daybreak in
most locations other than the eastern Florida Big Bend - including
Tallahassee. There could be wind chills close to advisory criteria
(20 degrees) in parts of southeast Alabama, but the spatial and
temporal extent is expected to be too limited for an advisory.



[Through 00Z Saturday] MVFR CIGS at ECP, TLH, and VLD will quickly
improve overnight, with clearing skies late tonight and into
tomorrow at all terminals. Breezy northwest to north winds will
continue, but frequent gusts are not currently expected.


.Prev Discussion [403 PM EST]...

.Short Term [Friday Through Saturday Night]...

The short range forecast will feature a broad upper level trough
across the northern two-thirds of the country, with several
shortwaves forecast to move through it. One of these shortwaves
will pass through the Tri-State region un-noticed tomorrow as deep
layer dry air will preclude any rainfall or cloud cover. At the
surface, high pressure will move east from the Middle Mississippi
Valley, into the Mid-Atlantic through Saturday night.

On Friday, continued CAA will keep daytime highs capped in the
lower 50s across southeast Alabama, up to around 60 degrees near
Cross City.

Friday night will most likely be a bit colder than tonight by
virtue of the fact that afternoon highs will be cooler across the
region. However, by Friday night winds will be veering northeast,
effectively putting an end to any CAA. Further, the calm center
of the ridge will be well to our north, also keeping us from
realizing the true potential of the cold airmass as indicated by
the dewpoint. Expect low 30s across southeast Alabama, gradually
increasing to the southeast where upper 30s are forecast for Cross
city. With the little bit of wind expected, temperatures will most
likely feel about 5 degrees colder than they are.

Saturday and Saturday night will feature moderating temperatures
as a weak, low amplitude ridge builds in aloft and surface flow
veers east, and then southeast. Expect highs between the upper 50s
to middle 60s across the same northwest to southeast gradient
mentioned above. Overnight lows will be closer to seasonal

.Long Term [Sunday Through Thursday]...

Starting on Sunday, the broad upper-level trough will begin to
amplify as two shortwaves dive southeast out of the Four Corners
region and the Saskatchewan/Manitoba border. At the same time, a
weak southern stream anomaly will initiate Gulf cyclogenesis along
the TX/LA border which will eventually link up with the amplifying
northern stream trough and move through the Tri-State region late
Sunday night through Monday. This system will bring us our best
chance for rain in a while, with average accumulations between 1-2
inches expected, at least across the western half of the region. In
it`s wake, cold Arctic high pressure will plunge southeast into the
region and likely bring us the coldest air of the season. Confidence
continues to increase that much of the region will experience lows
in the mid- to-upper 20s Tuesday night and possibly again on
Wednesday night.


Advisory level winds will be a bit delayed this afternoon, but are
still expected by this evening and will spread east through the
night. By midday tomorrow, advisory conditions will cease with on-
and-off cautionary level winds expected through Friday night.
Thereafter, winds and seas will fall to below headline levels
until our next, stronger frontal system approaches early next

.Fire Weather...

A much drier air mass will arrive on Friday, and durations of low RH
may approach red flag criteria in SE AL during the afternoon.
However, the latest guidance has come in with higher RH values so
there is continued uncertainty as to whether red flag conditions
will develop. Therefore, we have maintained the Fire Weather Watch
for one more model cycle, and the watch should either be cancelled
or upgraded tonight. We did cancel the fire weather watch for Leon
and Wakulla Counties with greater certainty that RH criteria would
not be met, along with the possibility that ERC criteria would not
be met either. RH values will recover this weekend, with a wetting
rain expected Sunday Night into Monday. The next chance of red flag
conditions would be Tuesday or Wednesday behind the cold front.


With only light rain expected today over the western half of the
area, river levels will remain well below flood stage. The
stronger frontal system forecast to arrive late this weekend into
early next week has the potential to bring rainfall amounts on the
order of 1 to 2 inches to the region, though at this time the
highest amounts appear as though they will stay northwest, out of
the local river system.


.Preliminary Point Temps/PoPs...

Tallahassee   36  54  34  62  44 /  10   0   0   0   0
Panama City   39  54  38  61  49 /  10   0   0   0  10
Dothan        30  50  31  57  39 /  10   0   0   0   0
Albany        32  52  30  58  40 /  10   0   0   0   0
Valdosta      37  55  34  61  43 /  10   0   0   0   0
Cross City    44  59  38  66  48 /  10   0   0   0  10
Apalachicola  39  56  42  61  50 /  10   0   0   0  10


.TAE Watches/Warnings/Advisories...

FL...Freeze Watch from late Friday night through Saturday morning for
     Calhoun-Central Walton-Holmes-Inland Bay-Inland Walton-

     Freeze Warning from 2 AM to 8 AM CST Friday for Central Walton-
     Holmes-Inland Walton-Jackson-Washington.

GA...Freeze Watch from late Friday night through Saturday morning for

     Freeze Warning from 3 AM to 9 AM EST Friday for Baker-Calhoun-

AL...Freeze Watch from late Friday night through Saturday morning for

     Freeze Warning from 2 AM to 8 AM CST Friday for Coffee-Dale-

     Fire Weather Watch Friday afternoon for Coffee-Dale-Geneva-Henry-

GM...Small Craft Advisory until 10 AM EST Friday for Apalachee Bay-
     Coastal waters From Ochlockonee River to Apalachicola FL
     out to 20 NM-Coastal waters from Suwannee River to Keaton
     Beach FL out 20 NM-Coastal waters from Apalachicola to
     Destin FL out 20 NM-Waters from Suwannee River to
     Apalachicola FL from 20 to 60 NM-Waters from Apalachicola
     to Destin FL from 20 to 60 NM.



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