Area Forecast Discussion
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847
FXUS62 KTAE 170638
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
238 AM EDT Sun Aug 17 2014

.Near Term [Through Today]...

The 10 pm EDT regional surface analysis showed a weak warm front
from south GA to AR, which separated a maritime tropical airmass
(typical for the Gulf Coast this time of year) to the south from
warm, relatively dry air to the north. The western extent of the
Bermuda ridge was building across the southern FL Peninsula and
eastern Gulf of Mexico. Vapor imagery and upper air data showed a
ridge that was nearly coincident with the aforementioned surface
ridge, a belt of westerlies across much of the Southeast, and a weak
short wave trough over the FL Panhandle. The zone of abnormally-low
PWAT values across our forecast area on Saturday were beginning to
retreat to the northeast, as PWAT values over the FL Panhandle were
already near climatology, with even (somewhat) higher values
upstream across the central Gulf Coast.

We expect a return to more typical summertime rain chances today as
the warm front lifts north of our area and deep layer moisture and
CAPE return. The highest PoP, 50%, is along and west of a line from
Tallahassee to Dothan. The PoP decreases to 20% around Albany,
Tifton, and Cross City, where the moisture will take longer to
return and mesoscale forcing will be lacking. This forecast is a
blend of the latest GFS, NAM, and ECMWF MOS and locally-run Ensemble
of Convection Allowing Models (ECAM). Although the large-scale
environment doesn`t appear favorable for organized severe storms
(due to relatively weak winds aloft and a lack of forcing), some of
the CAMs are forecasting updrafts of 24 m/s (where the highest PoP
is). This suggests at least a small chance (5% within 25 miles of a
point) of a marginally severe thunderstorm this afternoon. High
temperatures will be in the mid 90s inland; around 90 at the
beaches.


.Short Term [Tonight Through Tuesday]...

Monday will feature a blend of early morning offshore convection,
followed by the seabreeze front generating storms over land during
the afternoon. In the southwesterly flow regime, depending upon
how much offshore convection moves inland early on, it could
disrupt a well defined seabreeze front. This would mean that we
may receive most of our storms early in the day rather than later.
Regardless of exactly how this plays out, the best coverage of
storms will be across north Florida and extreme southwest Georgia.
Monday night into Tuesday morning as shortwave will brush our
northern Georgia and Alabama counties and provide a chance for
showers and thunderstorms overnight. The shortwave will elongate
over the region on Tuesday and provide a focus for showers and
thunderstorms. Expect a widespread scattering of storms on
Tuesday, not related to the seabreeze.


.Long Term [Tuesday Night Through Sunday]...

Stacked high pressure through the period will allow the sea-breeze
circulation will once again become the main driving force for our
local weather. With a drier than normal airmass in place, chances
will be somewhat lower than climo and temperatures will be slightly
warmer than climo. Highs will be in the mid 90s, low 90s along the
immediate coast, and lows will be in the mid 70s, upper 70s along
the immediate coast.

&&

.Aviation...
[Through 06Z Monday]

VFR conditions and light winds are expected- except for brief
periods of MVFR vis around dawn. Scattered SHRA/TSRA will develop
near the FL Panhandle coast around dawn, then spread inland. KECP
has the highest chance of SHRA/TSRA in the morning, and KTLH and
KDHN in the afternoon. Elsewhere we expect the storms to be more
isolated. Winds across the region will be SW around 10 KT by late
morning, except briefly stronger and gusty in TSRA.

&&

.Marine...

Modest southwesterly flow will near cautionary levels at times
over the next couple of days. This will be especially true in the
afternoon near the coast. By Wednesday, the surface ridge should
move closer to our waters, yielding calming winds. Expect
widespread morning showers and thunderstorms for at least the next
few mornings.

&&

.Fire Weather...

Red Flag conditions are not expected for the next several days.

&&

.Hydrology...

Significant rainfall is not expected over the next several days
and all area rivers should remain below action stage.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   95  75  93  75  95 /  50  20  60  10  40
Panama City   89  79  90  79  90 /  50  20  50  20  30
Dothan        93  75  94  75  93 /  50  30  50  20  40
Albany        96  75  94  76  94 /  20  30  40  20  40
Valdosta      95  73  94  74  95 /  30  20  60  10  40
Cross City    93  74  92  74  93 /  20  20  50  20  20
Apalachicola  89  79  90  80  90 /  30  30  40  20  30

&&

.TAE Watches/Warnings/Advisories...

FL...None.
GA...None.
AL...None.
GM...None.

&&

$$

NEAR TERM...FOURNIER
SHORT TERM...HARRIGAN
LONG TERM...MOORE
AVIATION...FOURNIER
MARINE...HARRIGAN
FIRE WEATHER...FOURNIER
HYDROLOGY...HARRIGAN






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