Scientific Forecaster Discussion
fxus62 ktae 140200
Area forecast discussion
National Weather Service Tallahassee Florida
900 PM EST Fri Dec 13 2019
A line of strong thunderstorms along and south of a warm front is
currently over the Gulf waters south of Panama City. These storms
should remain over the marine waters over the next couple hours.
Thereafter, there is the potential for them to move ashore into
the slight risk area outlined by spc, generally points southeast
of a Valdosta to Apalachicola line. The Southeast Florida Big Bend has
the greatest potential for severe weather overnight, including
damaging winds and a couple tornadoes. Otherwise, dense fog will
be an issue north of the warm front, from Berrien to Lafayette
counties and points southeast, excluding Dixie County however. A
dense fog advisory is in effect for this area through 3 am et,
when a line of showers and thunderstorms should mix the lower
atmosphere sufficiently to disperse the fog.
A line of thunderstorms is expected to move through the marine
area this evening and into tonight. This line as the potential to
produce brief, gale force wind gusts and even a waterspout. The
thunderstorms should exit the marine area by Saturday morning with
the next chance of precipitation Monday night. Tranquil boating
conditions are expected on Sunday. Thereafter, winds and seas will
become elevated, with advisory level conditions expected by mid-
Previous discussion [623 PM est]...
Near term [through tonight]...
A nearly stationary front is situated south of the Florida
Panhandle and Big Bend with the County Warning Area remaining in a limited area of
surface based instability. With this, activity has been limited so
far today and mainly just scattered showers for anything that did
develop earlier today.
As a shortwave moves across the southeast tonight a line of
showers and thunderstorms is expected to push across the County Warning Area this
evening into tonight. While the shear is sufficient across the
area, instability has been limited. This should increase though
ahead of the line with enough instability mainly across the
Florida Big Bend for damaging wind and/or a tornado or two. The
highest threat area from Storm Prediction Center is from Crawfordville to Valdosta and
eastward - that area is included in a slight risk, with the
marginal risk extending westward to seaside to Donalsonville to
Fitzgerald. The severe threat should diminish by 3am et.
Short term [saturday through Sunday night]...
A few light showers will be possible behind the front on Saturday
but the severe threat should end before the beginning of the short
term. Upper level flow will become zonal by Saturday night while
high pressure builds at the surface. The upper level flow will
become southwesterly late in the short term as the next system
dives into the plains. Highs will be in the 60s. Lows tonight will
be in the upper 40s to upper 50s, but only in the 40s (except 50s
along the coast) Sunday morning behind the front.
Long term [monday through friday]...
Deep layer high pressure will be off to our east by Monday, but
will still be close enough to provide US with one more fair weather
day, and a warm one at that. Daytime highs should be in the mid 70s
in most areas. The next frontal system will push through the area on
Tuesday. Shear profiles and instability parameters indicate at least
the potential for severe storms. The favored Mode is hard to call at
this time, but supercells and bowing line segment both appear
possible. Behind this next front, a cold airmass will settle across
the forecast area. Thursday morning appears to be the coldest with a
widespread light freeze expected for inland areas and the southeast
Big Bend. Daytime highs will be in the 50s Wednesday and Thursday
with a warm up to seasonal temperatures on Friday.
[through 00z sunday]
Areas of dense fog have developed ahead of the main convective
line with LIFR conditions at most terminals. The line of
thunderstorms should March from northwest to southeast across the
Aerodrome overnight, reach dhn by around 01-02z and vld by 05-07z.
While convection is moving through, ceilings may lift to MVFR for
a time, but IFR is expected to return after the storms depart
with clearing not occuring until after 14z.
A storm system will move through the region tonight with widespread
showers and thunderstorms. Drier conditions are expected through the
remainder of the weekend. The next storm system will approach the
region on Monday night. Red flag conditions are not expected for the
next several days.
Rainfall amounts with the event this evening and tonight will be
limited to less than one inch with isolated higher amounts.
Widespread flooding is not expected, however a few river points
(preston and Dawson at Kinchafoonee creek and Leesburg at Muckalee
creek) could reach action stage if isolated higher amounts are
Spotter information statement...
Spotter activation is requested. Spotters should safely report
significant weather conditions and/or damage by calling the office or
tweeting US @nwstallahassee.
Preliminary point temps/pops...
Tallahassee 53 65 43 68 49 / 100 0 0 0 0
Panama City 53 64 50 69 61 / 100 0 0 0 0
Dothan 48 60 41 65 51 / 100 0 0 0 0
Albany 49 60 40 63 47 / 100 10 0 0 0
Valdosta 54 63 41 67 48 / 100 10 0 0 0
Cross City 58 68 45 70 53 / 80 10 0 0 0
Apalachicola 55 65 51 67 61 / 100 10 0 0 0
Florida...dense fog advisory until 3 am EST Saturday for coastal Jefferson-
coastal Taylor-inland Jefferson-inland Taylor-Lafayette-
Georgia...dense fog advisory until 3 am EST Saturday for Berrien-Brooks-