072
FXUS64 KHUN 121102
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
602 AM CDT Wed Mar 12 2025

...New AVIATION...

.NEAR TERM...
(Today)
Issued at 357 AM CDT Wed Mar 12 2025

Based on recent days, cool guidance overall and forecast guidance
showing 925 mb temperatures climbing to between 16 and 17 degrees
in most areas, raised high temperatures from NBM guidance a few
degrees into the upper 70s. It also looks like dry air aloft will
again help to lower dewpoints towards noon and into the mid
afternoon hours more than ensemble guidance is showing. Thus,
lowered dewpoints to account for this. The combination of higher
temperatures and lower dewpoints will likely drop relative
humidity values in the afternoon to between 19 and 25 percent.
KBDI values remain less than 300. This is a good thing since winds
will be from the southwest around 10 mph gusting to between 15
and 20 mph at times. No appreciable cloud cover is expected today.

&&

.SHORT TERM...
(Wednesday through Friday night)
Issued at 905 PM CDT Tue Mar 11 2025

A near carbon copy of Tuesday is expected on Wednesday. Southwest
flow from the surface to 8h along with sunshine will push
temperatures into the middle to upper 70s for most areas. The next
upper level low will quickly emerge out of the Desert SW and into
OK/TX Wednesday afternoon. This will quickly produce upper level
diffluence and UVVs across the lower MS Valley Wednesday evening,
with steep mid level lapse rates. EML and elevated convection
will spread east into western and northwest AL after 06Z, and
across southern middle TN and the rest of north AL Thursday. A few
strong thunderstorms may produce hail with this activity into
Thursday, perhaps becoming briefly surface based looking at
forecast soundings before ending. The precipitation and clouds
will temper high temperatures into the upper 60s to lower 70s
Thursday afternoon.

A 5h ridge axis will shift east across the region early Friday as
the potent storm emerges in the central Plains. This will produce
expanding mid and upper level diffluence Friday afternoon into
Friday night as the upper low and intense surface cyclone pivot
northeast into northeast KS or southeast NE. Strong -divQ along
the dry line will force deep convection into MO and northern AR
Friday evening. Weaker QG forcing further south will likely result
in more isolated to scattered cellular convection in the lower MS
valley. This will race northeast and if the CIN layer can erode in
the weaker forcing, supercellular storms would be the favored
storm type due to a strongly sheared profile and favorable
hodographs. In any event, a larger plume of moisture and CAPE will
overspread the area from southwest to northeast by early Saturday
morning.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 905 PM CDT Tue Mar 11 2025

An active weather pattern to start the weekend is forecast for the
Tennessee Valley. A negatively tilted upper level trough over the
Plains will translate east on Saturday. Strong southerly flow in the
low levels will advect in moisture from the Gulf raising sfc
dewpoints into the lower 60s. A sfc low is forecast to develop
across MS during the morning hours before it ejects to the north and
east. As a result, strong dynamically driven forcing is expected to
generate widespread thunderstorms, some of which could become severe.
Storms should begin to develop around lunchtime in our western zones
and then spreading eastward through the afternoon. The threat for
severe weather should end in our eastern areas shortly before
midnight.

Ensemble forecast soundings have the mean instability between
750-1000 J/kg. However, looking at the higher end probabilities shows
1500-2000 J/kg of CAPE. Combined with 40 kts 0-1 km shear, 60 kts 0-3
km, and good curvature in the vertical shear profile, severe storms
appear favorable in this environment. Given the shear parameters,
tornadoes and damaging winds are the main concern, but if the higher
end CAPE values become realized then there would be some potential
for severe hail. Some limiting factors in the severe weather could
be the actual sfc low pressure track with a further south and east
track limiting some of the severe potential, but at the same time
increasing the heavy rain threat. However, with the latest few
ensemble runs, this solution appears less likely.

By the second half of the weekend, the upper level trough lifts to
the north and east bringing in some ridging across the central CONUS
to begin next week. Northwest flow Sunday and Monday will result in
near seasonal temperatures with highs in the lower 60s and overnight
lows in the upper 30s to lower 40s. By Tuesday, another system drops
down across the Rockies shifting the upper level ridge axis further
east. This will bring back southwesterly flow and hence warmer
temperatures with highs on Tuesday returning back into the 70s.

&&

.AVIATION...
(12Z TAFS)
Issued at 602 AM CDT Wed Mar 12 2025

VFR conditions are expected throughout the TAF period. SW winds
will increase to around 10 knots gusting to between 15 and 20 mph
after 16Z. Then expect winds to lessen to around 5 knots this
evening. High/Mid level CIGS should push into both terminals after
6Z.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...None.
TN...None.
&&

$$

NEAR TERM...KTW
SHORT TERM....17
LONG TERM....GH
AVIATION...KTW