Flash Flood in Alabama, September 2, 2025

Area Forecast Discussion
National Weather Service Huntsville AL
813 AM CDT Tue Sep 2 2025

...New NEAR TERM, SHORT TERM...

.NEAR TERM...
(Rest of Today and Tonight)
Issued at 813 AM CDT Tue Sep 2 2025

A shortwave in northwest flow at 5h is aiding expansion of
multiple clusters of showers and thunderstorms this morning. This
trend will persist through the day, with the main hazard being
ponding of water and a low risk of isolated flash flooding (WPC
marginal risk). Clouds and precipitation will lend to keeping
temperatures in the upper 70s to lower 80s for most areas for
afternoon highs. A decrease in rain activity will occur after
sunset, but chances pick up again late tonight as yet another
upper level impulse arrives. Overnight lows in the lower 60s are
forecast.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 813 AM CDT Tue Sep 2 2025

Wednesday will continue to present low chances of showers and
thunderstorms. With added sunshine as compared to Tuesday,
instability may become a bit greater, so a strong thunderstorm or
two cannot be ruled out. A stronger upper low will be digging into
the Great Lakes area by late Wednesday into Thursday, drawing a
stronger cold front and shortwave southeast through the eastern
Corn belt into the Ozarks, then east through the OH Valley into
the central and eastern TN Valley on Thursday. The tail end of
the cold front will bring a line of thunderstorms southeast into
eastern and middle TN into north AL Thursday afternoon. Weaker
forcing along this portion of the front may limit the southwest
extent of thunderstorms Thursday. Thus, PoPs will range 20-30% in
northwest AL and 40-60% in southern middle TN and far northeast
AL. The frontal boundary never passes through the local area, thus
temperatures will remain in the 60s Thursday night.

&&

.LONG TERM...
(Friday through Monday)
Issued at 1044 PM CDT Mon Sep 1 2025

A little bad news for the fans of early fall weather, the long term
pattern looks a little warmer than previously expected as the work
week comes to a close and we head into the weekend. The upper trough
axis will pivot east of the area as an additional wave starts to dig
south over the Great Lakes toward the weekend. A strong cold front
will push south through the OH River Valley and approach the TN River
Valley late Friday into Saturday but is expected to stall near or
just to our north. Where exactly this front stalls will have a
fairly big impact on the temperatures as areas south of the front
will experience temps in the upper 80s to lower 90s where areas north
of the front will drop to the 70s and lower 80s. Friday looks to be
the warmest day with highs in the upper 80s to mid 90s. With the
drier air in place, heat indices are expected to stay pretty close to
air temperatures so we are not expecting any heat related headlines
currently. The front is forecast to move little over the weekend
and will feature temps in the 80s with a low chance for rain and
thunderstorms on Saturday. Overnight lows will fall into the 50s and
lower 60s Saturday and Sunday nights before a pattern shift begins to
bring in warmer conditions on Monday. Stay tuned for forecast updates
throughout the week!

&&

.AVIATION...
(12Z TAFS)
Issued at 649 AM CDT Tue Sep 2 2025

There have been no major changes to previous aviation forecast
reasoning, as current radar data depicts an expanding region of
rain and embedded TSRA btwn MSL-HSV, which will largely impact
MSL/12-16Z and HSV/14-18Z. Although storms are not expected to be
strong, AWWs for occasional lightning may be warranted at times. A
second round of convection may evolve to our northwest later this
aftn (which could potentially spread southeastward into northern
AL this evening), and PROB30 groups have been included for this
activity from 22-2Z. Outside of convection, we expect VFR conds to
prevail with cloud bases near 3500 ft for much of the day. Sfc
winds will remain from the SE at speeds arnd 5 kts today, before
becoming lgt/vrbl this evening.

&&

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

NEAR TERM...17
SHORT TERM....17
LONG TERM....25
AVIATION...70