Area Forecast Discussion
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FXUS62 KTAE 200733

Area Forecast Discussion
National Weather Service Tallahassee FL
233 AM EST Fri Jan 20 2017

.NEAR TERM [Through Today]...

Line of showers and embedded thunderstorms continues to move across
the region at this hour. The current meso-scale analysis shows a
sharp gradient of instability along the Florida Panhandle coast,
with generally 500-1000 J/KG of CAPE remaining off-shore. The latest
convective trends over the past hour continue to suggest that the
strongest storms will be confined to coastal waters and along the
shoreline over the next several hours. The latest CAM guidance
continues to suggest a weakening trend with this line over the next
several hours, with dry mid-level air intruding from the west and
inhibition increasing across the eastern half of the area.

The mid-level trough responsible for these showers and storms will
continue to lift northeastward across the Tennessee and Ohio Valleys
during the late morning and afternoon hours. Scattered shower and
thunderstorm development is expected, mainly during the afternoon
hours, as a result of continued low-level and surface southerly flow
and weak isentropic lift across the region. This activity is
expected to wane during the evening hours. Despite mostly cloudy
skies today, highs will generally run in the mid to upper 70s across
the region.

.SHORT TERM [Tonight Through Sunday]...

**The main story in the short term remains the possibility of severe
weather, with all facets of severe weather threats, for Saturday
through Sunday afternoon.**

Shortwave ridging will move by and off to the east Friday night
in response to the deepening longwave trough across the central
CONUS with a shortwave trough lifting northeastward across the
upper Midwest. Low level warm air advection, along with
convergence from the strengthening low level jet and increasing
vorticity advection, will spark an increase in showers and storms
Friday night across the northern Gulf coast and spreading inland
and eastward as a warm front moves inland Saturday. Initially,
CAPE and Shear across the area are low Saturday morning but begin
to ramp up beginning late morning. This is when our window of
opportunity opens up for severe weather. Day 2 SPC convective
outlook has most of our area in a slight risk for severe weather.
Again, all facets of severe weather are possible.

Closed upper low develops Saturday night across the TX/OK panhandles
and moves eastward to northern Mississippi Sunday afternoon and into
the Carolinas Sunday night. Although instability decreases through
the evening and overnight, strong wind fields will lead to an
increase in shear and helicity values. Large scale lift will
increase as well as the closed low gets closer with diffluence
aloft. Still expecting a squall line of sorts to move across much of
the CWA with damaging winds and isolated tornadoes possible. That
threat will linger into Sunday across the eastern and southeastern
half of the CWA before dry slotting decreases rain chances from west
to east later Sunday into Sunday night. Day 3 SPC convective outlook
has our area in an enhanced area for severe weather mainly east of
Mexico Beach to Marianna FL to Albany GA. Slight risk remains west
of this line.

.LONG TERM [Sunday Night Through Friday]...

Light rain may linger into Monday on the backside of the departing
low pressure system. A cold front will swing through Monday which
will knock our temperatures down to near seasonal averages. Slightly
warmer temperatures expected Wednesday as surface high pressure
moves by but a fast moving cold front will bring another chance for
rain beginning Wednesday night.


.AVIATION [Through 06Z Saturday]...

Widespread area of RA continues to move eastward across the region,
with RA expected to clear at DHN and ECP within the next few hours.
All other TAF sites will see RA prior to daybreak. TLH and VLD are
currently seeing the development of low CIGS and fog respectively at
this hour, with these conditions expected to persist until RA moves
through later tonight. Low CIGS are expected and areas of fog may
redevelop as showers clear the area from west to east through
daybreak. VFR conditions to resume by late morning.



As the next low pressure system arrives Sunday, winds ahead of this
system will increase in response. Cautionary winds will develop
tonight with advisory winds by early Saturday. As the cold front
moves through the coastal waters Sunday, a further increase in winds
are possible. Gale force gusts are possible late Sunday through
Monday. Seas will climb to near 15 feet in response to these strong
winds across the far offshore waters. Winds will fall below advisory
level by Tuesday morning.



No concerns.



On average, 2-4 inches of rainfall is expected through Sunday night
across the area with isolated amounts approaching 6 inches. These
amounts will most likely fall over a long enough period that flash
flooding wont be a concern. Across area rivers, with these expected
rainfall amounts, rivers are expected to stay below flood stage.
There are a few rivers to keep an eye on however, such as the
Kinchafoonee Creek or Choctawhatchee River.



Tallahassee   77  64  74  64  75 /  40  50  80  80  70
Panama City   73  67  73  66  71 /  40  60  80  80  70
Dothan        76  63  74  61  71 /  40  60  90  80  70
Albany        77  63  74  62  73 /  50  50  90  80  80
Valdosta      77  63  75  64  75 /  30  40  80  80  80
Cross City    77  63  76  65  75 /  20  30  80  80  80
Apalachicola  73  67  73  67  73 /  30  50  80  80  70






NEAR TERM...Pullin
LONG TERM...Scholl
HYDROLOGY...Scholl is the U.S. government's official web portal to all federal, state and local government web resources and services.