Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 192024
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
324 PM EST Wed Nov 19 2014
.Near Term [Through Tonight]...
The Noon EST regional surface analysis showed an area of high
pressure centered over south GA. Even though temperatures aloft were
gradually warming, the extremely dry boundary layer, coupled with
calm winds, will allow surface temperatures to cool rapidly after
sunset. A widespread freeze is expected once again tonight, with a
hard freeze likely across much of the FL Big Bend, north FL, and
extreme south central GA. Lows in this area (away from the beaches
and cities) will be in the 20 to 25 deg range. Elsewhere, lows will
be in the upper 20s (except lower 30s at the beaches and cities).
.Short Term [Thursday Through Friday Night]...
After another cold start on Thursday morning, a warming trend will
begin across the region as high pressure centered over the region
lifts further northward up the Atlantic Seaboard and into the Mid
Atlantic. There`s the potential for one last night of freezing
conditions Thursday night as high pressure remains close enough to
the region to support calm winds, and with clear and dry
conditions, temperatures should fall into the lower 30s, over the
typically colder areas of the Florida Big Bend (Tallahassee-Perry-
Cross City). By Friday, easterly flow will transport Atlantic
moisture into the region. This pattern will result in temperatures
nearer to normal for late November with highs in the upper 60s and
lows in the mid 40s for Friday.
.Long Term [Saturday Through Wednesday]...
The weather pattern continues to transition on Saturday as a
strong mid level shortwave moves into Western Texas sparking
cyclogenesis across the Western Gulf. The global models are
in good agreement with the large scale details of this system,
transitioning into the Mid Mississippi River Valley on Saturday
night and then shifting rapidly northward into the Western Great
Lakes by Sunday night. As this system lifts northward, a surface
warm front will move north out of the Gulf of Mexico and move
through the Southeast. As is often the case with these events
following an arctic outbreak, there`s uncertainty whether the cool
stable airmass can be sufficiently displaced by a more moist
tropical airmass in time to overlay with the best forcing and
shear. The 19/12z GFS and to a lesser extent in the 19/12z Euro
show the warm front making decent progress inland, suggesting that
a narrow window for strong to severe storms is possible early
Sunday and into Sunday afternoon. Of course, confidence at this
time range is lower than normal, especially given how much
modification is necessary to our current airmass to be able to
support surface based convection.
As the system occludes over the Great Lakes on Sunday night, a
secondary shortwave will move across the Southern States helping
to push a cold front through the area on Monday afternoon. While
it is still conditional on the amount of instability in place, the
kinematic fields suggest the potential for strong storms with this
impulse as well, especially across the eastern half of the region.
By Tuesday, drier conditions appear likely as high pressure
becomes established across the Southeast. A reinforcing shot of
cooler air looks to arrive late Wednesday, suggesting the dry
conditions will persist through the rest of the week.
[Through 18Z Thursday] Unrestricted Vis & unlimited cigs will
continue. Winds will be light from the NE, generally less than
Light to moderate offshore will remain in place through Thursday
evening. Thereafter, the gradient will sharply tighten between a
high pressure area over the Mid Atlantic States and a developing
system over the Western Gulf. This will result in a prolonged
period of advisory conditions starting on Friday and continuing
The relative humidity will still be quite low on Thursday. This
combined with elevated ERC values for Leon and Wakulla counties will
lead to Red Flag conditions.
Also, due to relatively low mixing heights and light transport winds
on Thursday, dispersion indices will be low with values as low as
the upper teens over inland portions of northwest Florida. Moisture
levels will continue to increase later in the week with widespread
rains expected over the weekend.
The storm system for Saturday night through Monday will have the
potential to produce widespread rainfall amounts of 1.5 to 2.5
inches, with locally heavier amounts, especially if a secondary
impulse generates another batch of heavy rainfall on Monday
afternoon. However, this system still looks progressive enough at
this time, and given the rather dry conditions that have prevailed
through the fall, flooding does not appear to be a significant
concern outside of the urbanized areas. River levels are currently very
low, with plenty of capacity for runoff.
.Preliminary Point Temps/PoPs...
Tallahassee 23 63 31 68 45 / 0 0 0 0 10
Panama City 36 63 42 67 51 / 0 0 0 0 10
Dothan 30 61 38 65 44 / 0 0 0 0 10
Albany 27 62 35 67 43 / 0 0 0 0 10
Valdosta 25 62 34 65 46 / 0 0 0 0 10
Cross City 23 65 33 67 47 / 0 0 0 0 10
Apalachicola 35 63 39 66 52 / 0 0 0 0 10
FL...Hard Freeze Warning from 10 PM this evening to 8 AM EST Thursday
for Gadsden-Inland Dixie-Inland Jefferson-Inland Taylor-
Red Flag Warning until 6 PM EST /5 PM CST/ this evening for
Coastal Bay-Coastal Wakulla-Inland Bay-Inland Wakulla-Leon-
Red Flag Warning from Noon to 5 PM EST Thursday for Coastal
GA...Hard Freeze Warning from 10 PM this evening to 8 AM EST Thursday
AL...Red Flag Warning until 5 PM CST this afternoon for Coffee-Dale-