textproduct: Huntsville

KEY MESSAGES

Updated at 936 PM CDT Tue Sep 29 2026

- Medium to high (40-80%) chances of showers and thunderstorms will return to the forecast late this week into the weekend, with locally heavy rainfall the main concern.

- Temperatures will be on the rise through Friday, with increasing humidity yielding a Moderate Heat Risk (Level 2/4) in some areas Thursday and Friday.

NEAR TERM

(Rest of Today and Tonight) Issued at 1113 AM CDT Wed Sep 30 2026

Model guidance continues to hold the upper ridging strongly in place over the southeast today. 7.34 micron channel satellite imagery and 12Z Birmingham, AL 7 AM sounding data show very dry air in place around 850 mb to 700 mb. This area of drier air aloft will likely be reached as temperatures warm into the lower 80s today.

We are starting to see this in some area observations near and west of the I-65 corridor. This mixing of drier air will likely intensify into the afternoon hours, as temperatures continue to rise with abundant sunshine into the upper 80s to lower 90s. Expect RH values to drop into the 15 to 25% range in many areas later this afternoon.

925 mb winds from the SSE will likely begin to truly get rid of this drier air aloft over northern Alabama tonight as they increase to around 20 knots. This change and surface winds around 5 mph lasting a bit more into the evening hours should help to keep overnight lows warmer. Lows tonight should only drop into the upper 50s to lower 60s as a result. Not expecting even much patchy fog towards daybreak on Thursday.

SHORT TERM

(Thursday through Saturday) Issued at 1113 AM CDT Wed Sep 30 2026

Not much change overall on Thursday, though the center of the upper ridge shifts east over the Carolinas. NAM12, wants to produce some isolated showers over NW Alabama. However, given the strength of the upper ridging at that point and other dry model output, keeping with no PoP at this time. Likely not much warmer, given the center of the upper ridge is not directly over northern Alabama. Highs should again be in the upper 80s to lower 90s. It will continue to get more humid though, with afternoon dewpoints in the mid to upper 60s possibly. This will drive heat index values to around 100 degrees in the hottest locations.

The upper ridging continues to hold in place over the Carolinas Thursday night, as a decaying longwave axis begins pushing towards the Tennessee Valley from the Midwest region. Expect the trend of no rainfall to continue, but low level moisture will continue to advection into the region ahead of the approaching upper level trough axis. This should keep lows from dropping below the upper 60s to lower 70s.

By Friday morning the longwave trough axis continues to weaken in most guidance. The exception to this is the NAM12 guidance. ECMWF is the driest and holds off QPF the most into the day on Friday. Either way by the afternoon hours scattered showers and thunderstorms do look possible. Shear remains very weak 20 knots or less mostly, so strong storms do not look likely. However, with left over tropical moisture pooled ahead of the weak longwave trough axis, PWATS are forecast to climb to around or slightly above 2 inches.

However, most guidance continues to weaken the longwave trough axis Friday night, as the longwave trough axis moves southeast into the region. Forcing will be a bit of an issue, but the stalled weak front could produce some scattered areas of heavier rainfall.

LONG TERM

(Saturday through Tuesday) Issued at 1113 AM CDT Wed Sep 30 2026

To our west, an upper level trough will begin its swing through the TN Valley over the weekend. At the surface, an accompanying cold front will be pushing east. Weak WAA and strong low level moisture advection will be present along and ahead of this system. As such, as we move into Saturday morning we will have an incredibly moist environment present, priming us for a weekend of heavy rainfall and possible flash flooding concerns.

Through the weekend we will see dew points in the 70s and PWATs above the 90th percentile per BMX sounding climatology (2"+). This environment will be favorable for efficient rainfall production. With persistent forcing from Friday night through Sunday afternoon, high rain chances (60-80%) are in the forecast all weekend. Models indicate 2-4 inches of rain from Friday through Monday. Flooding concerns will arise if periods of heavy rainfall cause significant amounts of rain to fall in a short period of time. As such, WPC has issued a Slight Risk (level 2/4) for excessive rainfall for portions of the area on Saturday into Sunday. Some uncertainty remains regarding the QPF totals due to the fact the front and parent trough will be weakening as they move through. Should the system come through weaker than currently forecast, QPF amounts could trend down.

The front is currently forecast to pass during the day on Sunday, however low rain chances and cloud cover look to linger behind the front through Tuesday. The lingering cloud cover paired with the slow infiltration of cooler and drier air from the north will keep highs in the 70s and lows in the 50s for the start of the work week.

AVIATION

(18Z TAFS) Issued at 1122 AM CDT Wed Sep 30 2026

VFR conditions are expected throughout the TAF period.

HUN WATCHES/WARNINGS/ADVISORIES

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