textproduct: NWS Birmingham

KEY MESSAGES

Issued at 202 PM CDT TUE AUG 18 2026

- Heat: Major HeatRisk is expected to persist through the middle of the workweek. Heat indices are forecast between 103 to 109 degrees. A Heat Advisory is now in effect for portions of central Alabama through Wednesday.

- Thunderstorms: Isolated afternoon thunderstorms will remain in the forecast through Thursday, especially south of I-20. More organized rain chances will increase closer to the weekend, as a series of disturbances moves through the region.

DISCUSSION

(This afternoon through Monday) Issued at 202 PM CDT TUE AUG 18 2026

The upper-level ridge currently dominating the forecast will shift westward over the coming days, allowing a deep trough over the Midwest to influence the region. While temperatures will see a slight downward trend, Heat Advisory criteria are expected to persist in parts of the area through Wednesday before conditions ease by Friday into the weekend. As the Midwestern trough deepens, weak shortwaves will track across the region.

Organized rain is anticipated Friday through the weekend, though confidence regarding coverage and rainfall totals remains low. The deepening trough will facilitate the arrival of drier air, driving peak heat index values below advisory thresholds through the weekend. We increased rain chances above consensus for tonight and Wednesday, accounting for model performance limitations. High temperatures are anticipated to remain in the low to mid-90s into early next week.

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AVIATION

(18Z TAFS) Issued at 146 PM CDT TUE AUG 18 2026

Thunderstorms will remain in the forecast through 19/04z, with TCL, EET, and MGM maintaining PROB30 groups through then. Once thunderstorm activity diminishes, there is high confidence in VFR conditions for the remainder of the TAF period.

Note: AMD NOT SKED for AUO due to a weather observation outage.

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FIRE WEATHER

Dry conditions will continue, with MinRH values dropping into the 35 to 45 percent across western and southwestern counties. Winds will remain light through the period, with isolated to scattered afternoon showers and thunderstorms expected the next several days. Fire weather concerns will remain low over the next five days, but will begin to increase if rain-free conditions persist.

PRELIMINARY POINT TEMPS/POPS

Gadsden 69 96 72 97 / 0 10 0 10 Anniston 70 93 71 95 / 10 10 0 10 Birmingham 73 95 74 95 / 10 10 0 10 Tuscaloosa 74 99 75 99 / 20 10 0 20 Calera 73 95 73 96 / 20 10 0 20 Auburn 74 92 73 94 / 10 10 0 20 Montgomery 74 97 74 98 / 40 10 10 20 Troy 73 95 73 97 / 40 20 0 30

BMX WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 9 PM CDT Wednesday for the following counties: Autauga-Bibb-Chilton-Coosa-Dallas-Elmore-Fayette- Greene-Hale-Jefferson-Lamar-Lowndes-Marengo-Marion-Montgomery- Perry-Pickens-Shelby-Sumter-Tuscaloosa-Walker.

Heat Advisory until 9 PM CDT this evening for the following counties: Barbour-Bullock-Lee-Macon-Pike-Russell.