textproduct: Huntsville

KEY MESSAGES

Updated at 741 PM CDT Thu Aug 20 2026

- A Slight Risk (level 2 of 5) for severe thunderstorms exists this evening into the overnight with primary risk of damaging winds.

- Locally heavy rainfall, frequent lightning are also hazards with the thunderstorms tonight.

NEAR TERM

(Tonight and Friday) Issued at 741 PM CDT Thu Aug 20 2026

Convective clusters have redeveloped in middle and southwest TN into northeast MS that have now edged into far northwest AL this evening. This is along or just ahead of a cold front where dew points have pooled in the upper 70s to lower 80s. The primary hazards are gusty winds and locally heavy rain as MUCAPEs of 4000-6000 j/kg were located over much of the area, especially NW AL into western TN. Effective shear of 25-35kt was developing over northeast AR into southeast MO and western TN this evening as a 5h wind max of 30-40kt enters this region which will also aid the maintenance of these storms possible into the overnight hours. Patchy fog may develop late tonight into early Friday morning.

SHORT TERM

(Saturday through Sunday Night) Issued at 741 PM CDT Thu Aug 20 2026

Any remaining MCS clusters will shift south of the TN valley by Friday morning. There is a very low chance of a shower or thunderstorm along the cold front that will slip southeast into the TN valley on Friday, but the chance is less than 15%. Dry weather should last through Saturday. But then another northwest flow shortwave and cold front arrives Saturday night which may generate showers and thunderstorms in the eastern OH valley into eastern TN. It is unclear if thunderstorms will be able to develop southwest into the TN Valley Saturday evening or overnight. We will monitor model trends, but for now most areas will remain dry in the forecast. Dew points should drop into the 60s by Sunday behind this front which will be a welcome relief from the higher dew points we have experienced lately.

LONG TERM

(Monday through Thursday) Issued at 741 PM CDT Thu Aug 20 2026

A mean trough axis will remain in place over the eastern CONUS with a strong ridge over the southern Rockies into the southern Plains. This will keep a fairly active northwest flow regime over the central Plains and upper Midwest through the OH and TN valleys. This will keep at least low chances of showers and thunderstorms in play, with the big question begin details of MCS timing and intensity. It's far too early to discern this with much confidence, so will side with the NBM in this forecast. High temperatures will remain near normal in the upper 80s to lower 90s with lows in the 60s to around 70.

AVIATION

(00Z TAFS) Issued at 553 PM CDT Thu Aug 20 2026

There remains a low to medium chance of TSRA through ~04Z, with a risk of gusty winds, frequent lightning and +RA. Patchy BR or FG will develop by 10Z with a low chance of MVFR conditions at KHSV and KMSL through 13Z. VFR conditions are then expected through the rest of the period.

HUN WATCHES/WARNINGS/ADVISORIES

AL...None. TN...None.