textproduct: Huntsville

KEY MESSAGES

Updated at 1032 AM CDT Sat Aug 15 2026

- Dangerous heat will impact the Tennessee Valley through the middle of next week, with Major (Level 3/4) to Extreme (Level 4/4) heat impacts forecast.

- A Heat Advisory is in effect for all of northern Alabama and southern middle Tennessee through 7 PM Monday, with extensions potentially into the middle of next week.

- A Marginal (1 out of 5) risk for severe thunderstorms is forecast across Northern Alabama near and east of I-65 Monday afternoon.

NEAR TERM

(Rest of Today and Tonight) Issued at 1032 AM CDT Sat Aug 15 2026

An an upper level ridge continues to sit to our west, mostly dry conditions with above-normal temperatures will influence the Tennessee Valley. Our primary concern today will be heat as highs reach the upper 90s with heat indices in the 103-109 degree range. There is a low chance (less than 20%) in which some area of NW AL reach 100 degrees this afternoon. A Heat Advisory remains in effect through both today and tonight to account for the dangerous temperatures. Be sure to remain hydrated and seek shade when outdoors. Otherwise, a low chance (10% or less) of thunderstorms exists this afternoon in portions of far NE AL. If a thunderstorm is realized, it will present a low chance of gusty winds up to 50 mph.

SHORT TERM

(Sunday through Tuesday) Issued at 1032 AM CDT Sat Aug 15 2026

Under the aforementioned existence of an upper level ridge, the Tennessee Valley will remain in a heightened risk area for heat through at least early to mid next week. Our current Heat Advisory for all of northern AL and southern middle TN is valid through Monday evening, however, there is a low-medium chance it will get extended in time through Tuesday in future updates. Current highs through this period are forecast to be in the upper 90s with heat indices up to 110 degrees. Monday continues to be forecast as the hottest day of the period of concern, with heat indices nearing Extreme Heat Warning criteria. One factor to consider on Monday will be how much cloud cover associated with increased rain chances affect the temperatures. We are currently outlooked by the Storm Prediction Center for a Marginal risk (level 1 of 5) for severe weather Monday afternoon into the evening due to a risk for downbursts (and subsequent damaging winds) in NE AL and southern middle TN. Therefore, confidence remains higher in Extreme Heat Warning criteria being met along and west of I-65. Be sure to keep up with the latest forecast as we head into early next week and remain hydrated as heat continues to be the primary concern.

LONG TERM

(Monday night through Friday) Issued at 929 PM CDT Fri Aug 14 2026

The center of the ridge will begin to gradually flatten through the week, but Major (Level 3/4) heat impacts will continue through the work week. This is due to highs in the mid 90s and dewpoints in the mid to upper 70s creating heat index values in excess of 105 degrees each day. In addition to the heat, low chances (20-30%) of diurnally driven showers and thunderstorms will return to the forecast each afternoon Tuesday through Friday, thanks to the deep moisture in place. The one caveat would be if the ridge shifts a little further to the west, placing the area under northwest flow aloft. Should this play out, we may be more under the threat for MCS activity that rides along the edge of the ridge. We'll have to watch this in the days to come. Overall, hot and humid weather for the foreseeable future.

AVIATION

(18Z TAFS) Issued at 1141 AM CDT Sat Aug 15 2026

VFR conditions are forecast through the TAF period.

HUN WATCHES/WARNINGS/ADVISORIES

AL...Heat Advisory until 7 PM CDT Monday for ALZ001>010-016.

TN...Heat Advisory until 7 PM CDT Monday for TNZ076-096-097.