463
FXUS62 KTAE 260109
AFDTAE

Area Forecast Discussion
National Weather Service Tallahassee FL
809 PM EST Wed Dec 25 2024

...New UPDATE...

.UPDATE...
Issued at 808 PM EST Wed Dec 25 2024

The main change to the previous forecast was to increase rain
chances across the western half of the area tonight as an area of
rain pushes eastward from south-central Alabama. The latest
guidance is a little more bullish on some of this rain making it
into our forecast area, albeit on the light side. Some
thunderstorms have been noted well offshore of Mobile, but the
airmass over land is stable with dewpoints ranging from near 50
along the coast to as low as the mid 30s well inland. In addition,
MUCAPE is generally less than 100 j/kg over land. Thus, we
currently expect thunderstorms to remain offshore where MUCAPE >
500 j/kg exists. Areas of fog are also possible across the
southeast big bend tonight into Thursday morning.

&&

.NEAR TERM...
(Through Thursday)
Issued at 123 PM EST Wed Dec 25 2024

High pressure over the Northeast US and southeast Canada will
continue to push northeasterly flow into our area. A stratus deck
will arrive on the low-level east to northeast flow from the
Atlantic, spreading westward through the night into Thursday
morning. Meanwhile, a mid-level shortwave approaching from the west
along the Gulf Coast will help generate a low chance (20%) of
showers across the Florida Panhandle and southeast Alabama overnight
into Thursday morning. The clouds and increase in moisture will keep
lows warmer than the last few nights with 40s to low 50s.

This same cool, moist northeasterly flow riding underneath warm
southerly 850 mb flow will likely keep clouds in place for longer
tomorrow. Additionally, mid-level ridging builds in aloft during the
day, which will keep a lid on any mixing potential. This is a pretty
standard cold air damming/wedge setup for us. For those reasons, I`m
a bit pessimistic on the forecast for Thursday, keeping clouds
around longer and temperatures cooler. I leaned more on the hi-res
and MOS guidance which tends to perform a bit better in these
setups. Highs will range from the upper 50s along and north of US-82
to the low to mid 60s elsewhere. This could still be too warm as the
HREF paints about a greater than 50-80% chance that southwest GA
doesn`t get above 60. The southeast Big Bend may stand the best
chance of getting to the 70s, where the HREF has 40-60% chances of
that occurring.

&&

.SHORT TERM...
(Thursday night through Friday night)
Issued at 123 PM EST Wed Dec 25 2024

Upper level flow will become increasingly southwesterly through
the end of the week as low-level moisture slowly increases thanks
to southeasterly flow. A potent shortwave trough will pass
southwest to northeast across Arkansas and it should bring a
modest increase in southeasterly flow for the region late Thursday
into Friday. With increased low-level moisture, a weak warm-
advection regime, and some afternoon instability after morning fog
and low level clouds scour out, we`ll likely be able to squeeze
out a few isolated showers across the Panhandle and southeast
Alabama so have added 15% POPs to the forecast in that period.

High temperatures will be much warmer, by as much as 10 degrees in
some locations potentially, on Friday compared to Thursday and in
the low to mid 70s.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 123 PM EST Wed Dec 25 2024

The pattern will become much more active this weekend as a strong
shortwave pivots through the deep south within a broad
Central/Eastern CONUS trough. As the broad trough continues to
translate eastward at the start of the period, surface high
pressure shifts east and we`ll see increasing southerly flow and a
continued moistening trend into Saturday. Like Friday, this will
likely be enough to bring an increase in rain chances, but expect
more widespread coverage as the approach of the strong shortwave
and better moisture availability lead to more scattered showers
Saturday afternoon.

The strong shortwave and accompanying cold front move through the
forecast area on Sunday bringing scattered to widespread showers
and thunderstorms. While it`s still to early to determine given
the spread in guidance at these lead times, there appears to be at
least a non-zero chance for severe weather with this frontal
passage, especially looking at some of the strong solutions as
seen in the 12z Euro run this afternoon. However, given the
appreciable spread in the important details affecting our severe
weather risk, there are no outlined areas of concern at this time
from the Storm Prediction Center.

After the front moves through, a broad US trough will still
remain in place and with no appreciable cold airmass behind
Sunday`s shortwave/front, and several embedded shortwaves in the
broad trough, we`ll likely see a return to more rain chances at
some point early next week.

&&

.AVIATION...
(00Z TAFS)
Issued at 612 PM EST Wed Dec 25 2024

VFR cigs to start the TAF period with light easterly winds. Cigs
will begin to fall to MVFR heights following 06z tonight spreading
from east to west. VLD and TLH terminals may experience IFR
conditions with the low stratus that moves in. There is a slight
chance for rain showers affecting ECP later tonight. Patchy fog
may develop in the region but confidence is not high enough to
include in the TAFs.

&&

.MARINE...
Issued at 123 PM EST Wed Dec 25 2024

East and northeasterly flow will prevail through Friday around 10
to 15 knots with occasional periods of cautionary conditions
Thursday and into Friday as a weak system moves through the
southeast US and tightens the pressure gradient. Rain chances
will mostly stay out of the forecast until later this weekend as
one final system moves through. Winds shift to being out of the
south-southeast this weekend and then westerly behind the cold
front on Sunday but at this time there is still a doubt that we`ll
reach advisory level conditions.

&&

.FIRE WEATHER...
Issued at 123 PM EST Wed Dec 25 2024

Easterly transport winds around 10-15 mph on Thursday will
shift out of the southeast to south Friday into Saturday. Mixing
heights will increase across the area through the next several days,
which will result in increasing dispersions each day. Fair
dispersions are expected Thursday, becoming good Friday and
Saturday. Rain chances will increase from west to east over the area
during the next several days with the highest chances over the
western Florida Panhandle into southeast Alabama.

&&

.HYDROLOGY...
Issued at 123 PM EST Wed Dec 25 2024

First widespread rainfall is likely this upcoming weekend with
much of the region potentially picking up 0.5 to 1 inches of rain
as a frontal system passes by Saturday into Sunday. Isolated
rainfall amounts of 2 to 3 inches is possible, especially across
the Panhandle and southeast Alabama.

&&

.SPOTTER INFORMATION STATEMENT...

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.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   49  66  54  74 /  20  10  10  10
Panama City   51  67  56  73 /  40  30  10  20
Dothan        46  61  51  70 /  30  20  10  20
Albany        44  59  49  70 /  20  10   0  10
Valdosta      47  64  53  75 /  10  10  10  10
Cross City    50  70  55  78 /  10  10   0  10
Apalachicola  54  65  58  69 /  40  20  10  10

&&

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

$$

UPDATE...DVD
NEAR TERM...Young
SHORT TERM...Dobbs
LONG TERM....Dobbs
AVIATION...Montgomery
MARINE...Dobbs
FIRE WEATHER...Young
HYDROLOGY...Dobbs