NWS Area Forecast Discussion: For Tallahassee FL Area

000
FXUS62 KTAE 171841
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
241 PM EDT Thu May 17 2012

.NEAR TERM...
(Rest of today and tonight) After a mostly sunny morning and
partly cloudy beginning to the afternoon, a more robust CU field
is now developing over parts of the CWA. In fact, a fairly strong
storm with frequent lightning and likely some small hail has
already developed and moved eastward through Dixie County in the
FL Big Bend, and it now appears our focus for the remainder of the
afternoon and evening hours will be the developing storms to our
North. These cells, which are forming just to the north of our GA
counties, appear to have the most potential to become strong, with
an isolated severe storm not out of the question. This general
southward storm motion was picked up well in the the Hi-Res
Models, and we used our local Confidence Grids for PoPs tonight,
with the highest PoPs from 00 to 06 UTC, as most of the storms
should be diurnally driven, with some forcing from the Upper Low.
Not expecting much in the way of fog overnight with significantly
lower dewpoints across the CWA than yesterday, with possible
exception of any isolated pockets if any heavy rain falls after
sunset.


.SHORT TERM...
(Friday through Saturday night) On Friday, the weak upper level low
will continue to weaken further and slide east of the area. PoPs are
expected to be on the low side with upper support waning and drier
air moving in. The best chance for afternoon convection (30-40
percent) looks to be over the far eastern counties closer to the
weak upper level trough and higher moisture. On Saturday, surface
high pressure is expected to nose in from the north and reduce PoPs
further in both spatial area and magnitude, although an isolated
shower or thunderstorm is still possible across the eastern half of
the forecast area.

.LONG TERM...
(Sunday through next Thursday) At upper levels, broad cyclonic
flow will be in place across the Southeastern U.S. to begin the
long term period and this will continue through Tuesday. At the
surface, high pressure will be centered over the Mid Atlantic
states as an area of low pressure develops off the Southeast U.S.
coast. There are still model differences on just how this low will
evolve. However, there is some consensus between the latest runs
of the GFS and Euro that a weak low will remain fairly close to
the coast through Monday night. This would bring drier air from
the ridge into our western zones while allowing some influence
from the ECSB to the east. We therefore maintain daily low end
chances for TS through this period, slightly higher east than
west. With decent mid level lapse rates, and periods of DPVA
enhancing lift, we should see isolated strong storms each
afternoon. As the upper trough and surface low lift away,
surface high pressure will begin to settle southward and our
forecast will trend toward lower PoPs and slightly higher
temperatures.

&&

.AVIATION...
Thunderstorms will be the main concern for terminals this
afternoon. Storms should begin to develop in the eastern CWA
first around 19-21z and continue until nightfall. Therefore we
have MVFR conditions for ABY, VLD, and TLH during the late
afternoon, in anticipation that those terminals will see a brief
period of gusty winds and reduced vis from a cell or two.
Otherwise a scattered CU field and light northerly winds is
expected.

&&

.MARINE...
Winds and seas are expected to remain below headline criteria for
the next several days. Over the weekend, winds will reach their peak
when high pressure noses to its furthest south position across the
southeast part of the country and a surface low develops in the
extreme western Atlantic, tightening the pressure gradient locally.
The coverage of showers and thunderstorms is expected to remain on
the low side for the next several days.

&&

.FIRE WEATHER...
Although rain chances will be gradually on the decrease during
the next couple of days, and some drier air has moved in from the
north, it still appears that afternoon relative humidities will
remain above critical thresholds for at least the next couple of
days across the Tri-State Area.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   63  86  65  86  62 /  20  20  10  20  20
Panama City   65  87  67  83  65 /  10  10  20  20  10
Dothan        64  88  62  86  62 /  10  10  10  10  10
Albany        63  84  62  87  61 /  20  30  10  10  10
Valdosta      62  85  62  87  62 /  30  30  10  20  20
Cross City    63  87  62  86  63 /  30  20  20  30  20
Apalachicola  65  83  67  81  67 /  10  10  20  20  20

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...None.

&&

$$

Near Term/Fire Wx...Gould
Short Term/Marine...DVD
Aviation...Walsh/Gould
Long Term...Wool

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