Area Forecast Discussion
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FXUS62 KTAE 180006

Area Forecast Discussion
National Weather Service Tallahassee FL
806 PM EDT Sat Mar 17 2018


Isolated showers and thunderstorms will continue to dissipate this
evening. No significant changes were made to the forecast for
tonight during the evening update.



.NEAR TERM [Through Tonight]...

Showers and thunderstorms are developing across central Georgia,
southeast Alabama and into the Florida Panhandle where moisture
content and instability best compliment isentropic ascent at this
hour. This activity will continue to strengthen over the next few
hours and move ENE across the Wiregrass through the remainder of the
afternoon, yielding brief, heavy rain and gusty winds. Given the
magnitude of shear nosing into the region (30 to 40 kts of bulk
shear per the latest mesoanalysis), a strong storm or two capable of
producing damaging winds gusts is not out of the question this
afternoon. These storms will quickly weaken and diminish early this
evening with the loss of daytime heating. However, a moist boundary
layer, coupled with a weak surface winds, wet soils, and a pocket of
dry air between 850 and 500mb will yield areas of fog across the
region through mid-Sunday morning. Given widespread cloud cover
across the region overnight, low temperatures will only fall into
lower 60s.

.SHORT TERM [Sunday Through Tuesday]...

An active short-term period is expected with multiple rounds of
severe weather possible.

Starting tonight, a cold front will drop into the Southeast
associated with a shortwave moving through the Ohio Valley and
Mid-Atlantic. A shortwave moving through the Southern Plains
Sunday morning will help stall this front west/east across central
GA/AL. Convection will develop Sunday afternoon along the Gulf
coast seabreeze, as well as along the warm front, and will likely
consolidate across the interior Panhandle, southeast Alabama, and
extreme southwest Georgia late in the afternoon. A few storms in
this region may become severe, with the main threat being damaging
winds or marginally severe hail. SPC has placed this region in a
Marginal Risk for severe storms. The possible multi-round, main
event, will begin Monday morning as a weak shortwave passes over
the Southeast and convection develops along the coastal front and
spreads inland. Modest lapse rates, around 50 knots of deep layer
shear, and plenty of instability would favor a threat for damaging
winds and possibly some hail. The threat for tornadoes with this
first round remains low and should be confined closer to the
coast near the coastal front. Depending on the evolution of
morning/afternoon convection, if we`re able to destabilize enough
by the time the cold front arrives overnight the threat for more
widespread and stronger severe storms is possible. Shear profiles
and lapse rates are forecast to become more favorable, so it`s
just a question of the pre-frontal instability. All modes of
severe weather would be possible overnight with the main threats
being damaging winds and tornadoes, with the hail threat being a
bit lower. The threat for severe weather exists the southeast Big
Bend of Florida early to mid-morning Tuesday, with some post
frontal rain possible across AL and GA as another shortwave moves
through the Southeast on Tuesday.

.LONG TERM [Tuesday Night Through Saturday]...

A much quieter pattern is expected from mid-week to the weekend as
the eastern CONUS trough prevails aloft with ridging at the
surface. Expect highs and lows to be more seasonable with no rain

.AVIATION [Through 00Z Monday]...

Currently, SHRA/TSRA near DHN and ABY are expected to diminish
after sunset. VFR to MVFR conditions for the remainder of this
evening, becoming IFR/LIFR overnight with fog possible at all
terminals. Conditions will improve mid morning, though another
round of showers and thunderstorms is expected Sunday afternoon.
Winds will become light overnight into early sunday morning,
otherwise expect southwesterly winds to prevail around 10 kts.


Relatively light winds and low seas are expected through Sunday
night. Conditions will begin to deteriorate beginning Monday as
storms, winds, and seas increase ahead of our next frontal system.
Expect at least Cautionary conditions beginning Monday. Behind the
front on Tuesday, solid advisory conditions will overspread the
northeast Gulf and linger until Wednesday. Cautionary conditions
are expected for much of the remainder of the week.


Low RH values will return mid to late next week. Showers and
thunderstorms will be increasing in coverage this afternoon. Rain
chances will be elevated Sunday afternoon through Tuesday morning.


A couple chances for heavy rain will exist over the next 48 to 60
hours. The first round will be Sunday night across AL and GA as a
warm front lifts through the region. Another round is expected on
Monday as two waves of convection are expected. Both Sunday and
Monday, storms should be fairly progressive so heavy rain
shouldn`t sit over one place for too long. Average rainfall totals
through Tuesday will be around 0.75-1.5", with isolated higher
amounts up to 3-4". For the most part, flooding is not expected,
though if a sensitive basin gets targeted multiple times, some
minor localized flooding will be possible.


Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.



Tallahassee   60  82  66  79  67 /  10  60  40  70  50
Panama City   63  75  66  75  66 /  10  50  60  70  40
Dothan        59  78  65  78  62 /  30  80  60  70  40
Albany        59  79  63  78  64 /  20  30  70  70  40
Valdosta      60  83  65  78  67 /  10  40  60  70  40
Cross City    56  82  63  76  67 /   0  20  20  70  50
Apalachicola  64  75  67  73  67 /  10  40  50  70  50




NEAR TERM...Pullin
SHORT TERM...Harrigan
LONG TERM...Harrigan
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