textproduct: NWS Birmingham

KEY MESSAGES

Issued at 549 AM CDT SAT JUL 18 2026

- Thunderstorms: Medium to high rain and thunderstorm chances expected over the weekend.

- Heat: Minor to moderate heat risk through the weekend, transitioning to a major heat risk early next week with heat indices potentially reaching 105 degrees.

DISCUSSION

(Saturday through next Friday) Issued at 1100 PM CDT FRI JUL 17 2026

The synoptic pattern remains largely unchanged across the region, with a moist air mass residing over the Southeast. The axis of showers and thunderstorms is expected to shift toward the south and east, resulting in higher precipitation probabilities in those areas. Isolated convection remains possible across western sections as well, though coverage will likely be minimal. This evolution is in response to the main ridge slowly shifting eastward, maintaining our area on its eastern periphery.

In the Northeastern Gulf, a tropical disturbance will slowly meander, possessing a 10-30% chance of tropical development over the next several days. Currently, the system lacks significant organization or a concentrated low-level circulation. This, combined with model guidance that remains split between two primary scenarios, contributes to continued forecast uncertainty through the weekend and early next week.

The first scenario suggests that an eastward-moving trough will interact with the disturbance, steering it northeastward through Florida and Georgia. This would facilitate an influx of tropical moisture into Central Alabama, leading to increased rain chances on Sunday. This outcome typically occurs when a disturbance is sufficiently developed to be influenced by the mid-latitude flow. Should this pattern develop, the disturbance would track well to the east while the main ridge remains positioned just to the west.

The second scenario involves the system remaining in the Gulf for several days, effectively trapped by the ridge and drifting slowly westward. This would limit the inland moisture transport; however, isolated to scattered showers would remain possible daily as convergent bands move into the area. This scenario often occurs with weaker, smaller systems that lack the vertical depth necessary for the trough to influence their motion. This possibility is increasingly reflected in the short-term model consensus and warrants continued monitoring.

In either case, a gradual warming trend is expected Monday through Thursday. Daytime highs are forecast to reach the mid to upper 90s by Tuesday and Wednesday. However, uncertainty remains regarding these peak temperatures, as diurnal thunderstorm activity and potential tropical influences could mitigate daytime heating. Trends will be monitored closely, particularly for Tuesday and Wednesday, as heat indices may approach or exceed 105 degrees depending on temperature adjustments in subsequent forecasts.

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AVIATION

(12Z TAFS) Issued at 549 AM CDT SAT JUL 18 2026

Prevailing VFR conditions could be briefly interrupted by scattered afternoon thunderstorms after 18Z, prompting the inclusion of PROB30 for all sites. This activity could linger after 00Z at KMGM and KAUO due to a convective band rotating around a tropical disturbance in the northern Gulf.

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 a weak disturbance in the Eastern Gulf is expected across the area over the weekend, 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 91 73 92 73 / 30 20 60 20 Anniston 91 73 92 73 / 30 20 60 30 Birmingham 92 75 94 74 / 30 20 50 30 Tuscaloosa 94 75 95 75 / 20 20 30 20 Calera 94 74 95 74 / 30 20 40 30 Auburn 90 74 91 74 / 40 30 60 40 Montgomery 94 74 94 74 / 50 30 50 40 Troy 92 73 92 73 / 50 40 60 50

BMX WATCHES/WARNINGS/ADVISORIES

None.