272
FXUS64 KHUN 011820
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
120 PM CDT Mon Sep 1 2025

...New NEAR TERM...

.NEAR TERM...
(Tonight)
Issued at 120 PM CDT Mon Sep 1 2025

Scattered showers and a few thunderstorms have sprouted across
southern middle TN into north central and northwest AL. With
effective shear of 15-20kt, they remain very pulsy in nature.
Mid level lapse rates of 5-6 C/km are also keeping these rather
ordinary in nature. Not much in previous thinking that the showers
and thunderstorms will linger into the evening, but loss of
heating should deteriorate most of the activity.

Previous Discussion...
Issued at 919 AM CDT Mon Sep 1 2025

An inverted surface trough axis has shifted northwest into middle
TN and far northwest AL. Convergence along this axis will be the
focal point for the development of showers and perhaps a few
thunderstorms today, possibly lingering into tonight. Cold air
damming behind this trough axis was advecting dew points in the
50s from the Carolinas into GA and far east AL. This will limit
the chance of rain in our eastern counties today into tonight.
Afternoon highs will reach the upper 70s to around 80 along the
Cumberland Plateau, Sand and Lookout Mtn, to the upper 80s along
and west of I-65. Overnight lows will drop into the lower to
middle 60s.


&&

.SHORT TERM...
(Tuesday through Wednesday)
Issued at 919 AM CDT Mon Sep 1 2025

The trough axis will shift a bit further northwest on Tuesday,
but northwest flow and incoming weak shortwaves will tend to keep
at least a low to medium chance of showers and thunderstorms in
far northwest AL. A stronger shortwave will drop into the TN
valley Tuesday night, with multiple clusters of showers and
thunderstorms. With 5h winds increasing to 25-30kt and
southwesterly 8h winds of 15-25kt, some organization and longevity
of a possible MCS late Tuesday night into Wednesday morning.
Locally heavy rainfall will be the main hazard, especially on
Wednesday, and thus a Slight Risk of excessive rainfall outlook in
place. The clouds and precipitation will keep highs in the upper
70s to lower 80s Tuesday, and just a few degrees warmer on
Wednesday, but that still has much doubt depending on the MCS
evolution and longevity into Wednesday.

&&

.LONG TERM...
(Wednesday night through Sunday)
Issued at 1102 PM CDT Sun Aug 31 2025

The main feature to discuss in the long term will be a cold front
forecast to move into the area from the northwest on Thursday
morning. This front will stem from a low pressure system slowly
pushing eastward through the Great Lakes region, bringing an upper
level trough southeastward into the Ohio River and Tennessee
Valleys. Ahead of the front, on Wednesday into Wednesday night,
low to medium chances of showers/thunderstorms are forecast,
bringing a low chance of some stronger storms. CAPE continues to
look unimpressive, however, ~30-40 kts of shear coupled with
decent low level lapse rates (~7-7.5 C/km) will allow gusty winds
to be a threat in stronger storms. Additionally, PWATs up to
1.5-1.6" will be around the 75th percentile per OHX sounding
climatology and storm motion is forecast to be relatively fast
(around 35-40 mph). Therefore, flash flooding is not a concern at
this time.

After the front moves through on Thursday, dry and relatively cooler
weather is forecast to move in through the weekend into early next
week as sfc high pressure takes over the area from the north. Highs
are forecast to remain in the 80s with overnight lows dropping into
the 50s for most of the Tennessee Valley.

&&

.AVIATION...
(18Z TAFS)
Issued at 1145 AM CDT Mon Sep 1 2025

VFR flight weather conditions will prevail for most areas with
scattered to broken layers staying above 030agl except in and near
SHRA and TSRA. Isolated to scattered SHRA and TSRA are expected,
mainly in north central and northwest AL into southern middle TN.
Given uncertainty on coverage, have opted to include VCSH at both
KMSL and KHSV through 02Z. Low chances continue into tonight, but
too low to include at this time.

&&

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

$$

NEAR TERM...17
SHORT TERM....17
LONG TERM....HC
AVIATION...17