textproduct: NWS Birmingham

KEY MESSAGES

Issued at 603 AM CDT MON JUL 20 2026

- Thunderstorms: Medium to high rain and thunderstorm chances expected through Tuesday. Heavy rainfall will remain possible and localized flooding in the more persistent bands of rain.

- Tropical: Tropical Depression Two will continue to strengthen in the northern Gulf and move slowly to the west and northwest through the beginning of the work week. At this time, no significant impacts are expected for Central Alabama.

- Heat: Moderate heat risk Monday through Wednesday with heat indices reaching 105 degrees.

DISCUSSION

(Monday through next Sunday) Issued at 1049 PM CDT SUN JUL 19 2026

The work week begins with Central Alabama firmly under the influence of a broad high-pressure ridge centered over the Great Plains, which is gradually building eastward. This synoptic setup supports a "Major HeatRisk" across the South, with temperatures climbing into the upper 90s and heat indices reaching triple digits through the first half of the work week. Regarding heat, heat index values across the northwest counties (I-59 northward) may approach advisory thresholds. However, for the central corridor (I-59 to I-85), subsidence aloft may allow for lower surface dewpoints than model guidance suggests, potentially limiting the spatial coverage of the most oppressive conditions. Southern counties (I-85 and south) are expected to remain below advisory criteria as increasing cloud cover and convective debris from the Gulf system help to moderate temperatures.

While several shortwaves will bring frontal boundaries toward the Southeast by mid-week, the primary focus remains the tropical depression currently in the northern Gulf. This system is expected to intensify into a tropical storm by Monday morning. The steering environment is currently characterized by weak currents, but as the high-pressure ridge over the central U.S. builds mid-week, it will become the dominant steering feature. There remains uncertainty regarding the exact track: if the high pressure is robust and moves across the MS/AL region, the system will be forced westward toward Texas, keeping the most significant tropical impacts away from Central Alabama. Conversely, a weaker high-pressure ridge could allow for a more northwesterly track closer to the region. The official forecast currently reflects a blend of these guidance solutions pending further model consensus.

Impacts for Central Alabama are expected to remain minimal at this time, though the period from Tuesday night through Wednesday requires close monitoring. During this window, winds are forecast to transition to a southerly or southeasterly direction. While confidence is currently insufficient to warrant a Wind Advisory, largely due to model divergence regarding the system's intensity, gusty winds remain possible if the low maintains a track in closer proximity to our area. Regarding convection, isolated to scattered storms on Monday will likely transition into increased coverage by Tuesday night and Wednesday, particularly across our far southeastern counties, where the influence of the tropical moisture feed will be most pronounced. Across the broader CWA, instability will remain high, maintaining the potential for strong to isolated severe thunderstorms each day from Monday through Wednesday.

By Thursday, the synoptic pattern undergoes a significant shift as the aforementioned frontal boundary, pushed by a shortwave trough tracking through the Tennessee Valley, sweeps through the Southeast. This transition is expected to displace the lingering tropical moisture and shift the local flow to a northerly or northeasterly direction. This will effectively end the persistent triple-digit heat index threat, bringing slightly cooler and drier air into the region. The remainder of the period, from Friday through Saturday, should offer some relief from the oppressive conditions of the early week.

16

AVIATION

(12Z TAFS) Issued at 603 AM CDT MON JUL 20 2026

Prevailing VFR conditions are expected at all sites, but scattered afternoon showers and storms may temporarily reduce flight categories, Northern activity could begin by 18Z with southern activity expected after 20Z.

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

87/Grantham

FIRE WEATHER

The warm and humid air mass will continue through the next several days across Central AL. Increasing tropical moisture associated with Tropical Depression Two is expected across the area over the beginning of the work week, which will increase rain chances each afternoon, especially for the eastern half of Central AL. There are no critical fire weather concerns at this time.

PRELIMINARY POINT TEMPS/POPS

Gadsden 93 74 94 75 / 30 20 10 0 Anniston 93 73 93 75 / 20 10 20 0 Birmingham 94 76 95 76 / 20 20 10 0 Tuscaloosa 95 76 95 76 / 20 20 10 0 Calera 95 74 97 75 / 20 10 20 0 Auburn 93 74 90 75 / 20 20 50 0 Montgomery 96 75 94 75 / 20 10 50 10 Troy 93 73 90 74 / 20 30 60 10

BMX WATCHES/WARNINGS/ADVISORIES

Heat Advisory from 10 AM this morning to 9 PM CDT Tuesday for the following counties: Bibb-Blount-Etowah-Fayette-Greene-Hale- Jefferson-Lamar-Marion-Pickens-Shelby-St. Clair-Sumter- Tuscaloosa-Walker-Winston.