textproduct: NWS Birmingham

KEY MESSAGES

Issued at 246 PM CDT MON SEP 7 2026

- Heat Indices: While slightly cooler temperatures arrive today, heat indices will still reach 100-105 degrees west of I-65. Humidity levels will gradually become lower, but interests should continue to practice heat safety.

- Rain and Storms: Drier conditions today through Wednesday will shift rain activity toward the south. By the end of the week, increasing moisture levels will lead to a better chance for afternoon showers and storms.

DISCUSSION

(This afternoon through Sunday) Issued at 246 PM CDT MON SEP 7 2026

A very interesting mesoscale setup for late summer is currently ongoing, with a strong easterly wedge moving in from GA. Surface high pressure centered over the Appalachians and mid-Atlantic region will keep a strong wedge in place at least through midweek. Isentropic upglide due to easterly/southeasterly winds at the surface and northerly to northwesterly winds aloft (700 to 500mb) has allowed for a stratus cloud deck to develop across eastern and northeastern Alabama, along with much of northern Georgia. With the wedge and clouds moving in from Georgia, temperatures are actually still in the 80s at Anniston and Gadsden, while hot and humid low to mid 90s are observed elsewhere. Moisture pooling ahead of the wedge front has actually spiked dewpoints into the low and mid 70s along and west of I-65, pushing heat indices close to Heat Advisory criteria. We should see the easterly flow gradually work to the west this afternoon to provide a few degrees of "relief" but conditions will still feel quite oppressive through the afternoon hours before easterly winds of 10 to 15mph arrive late this afternoon and into the evening hours.

In terms of rain chances this afternoon and evening, we'll still have to keep an eye on a few storms this afternoon that will be capable of producing gusty winds again, but coverage will be limited north of the I-20 corridor due to a slug of dry air moving in aloft and capping the environment. The dry air was very pronounced on the 12z KBMX sounding above 500mb. With very steep low-level lapse rates, we'll see mainly pulse storms this afternoon with updrafts quickly building and collapsing. With the dry air aloft, microburst-type wind gusts of 40 to 50mph are likely within stronger storms. As storms diminish with the loss of daytime heating this evening, easterly winds are expected to continue overnight, instead of the usual calm or variable winds we've been used to this summer. The strong gradient from the easterly wedge is forecast to keep the boundary layer mixed, with sustained easterly winds of 5 to 10mph. A few spots in the higher elevations across the eastern and northeastern counties may actually observe some wind gusts between 15 and 20mph overnight.

The easterly wedge will remain in place through the day on Wednesday, as the 500mb ridge builds in aloft. Rain chances are forecast around zero as a result on Tuesday, with 20 to 30% chances of a shower or storm along and south of I-85 by Wednesday. Otherwise we'll stay hot in the 90s, but stay below Heat Advisory criteria thanks to slightly drier air moving in with the easterly wedge. Guidance today is hanging on to the 500mb ridge a little longer through the end of the week which may keep rain chances on the lower end through Thursday with gradually increasing southerly moisture both at the surface and aloft on Friday. As mentioned yesterday, a cold front moving southeast toward the Ohio Valley is advertised to now lose upper support and stall to our northwest by Friday afternoon. Increased diurnally-driven rain chances would therefore be in the cards for Friday through the weekend with highs remaining above normal in the low to mid 90s.

56/GDG

AVIATION

(18Z TAFS) Issued at 104 PM CDT MON SEP 7 2026

VFR conditions are forecast to prevail through the forecast period. Winds will gradually become easterly by this afternoon, prevailing around 10 knots. A few gusts between 15-20 knots can't be ruled out, especially for AUO and MGM. PROB30 remains in the forecast for most terminals, as scattered SHRA/TSRA can be expected during the peak heating of the afternoon. Winds will actually remain in the forecast during the overnight hours as easterly flow picks up, with a few gusts returning once again by Tuesday afternoon.

Note: AMD NOT SKED at TCL due to missing observations.

56/GDG

FIRE WEATHER

Minimum RH values are expected to stay above 40% through next week. While daily rain chances will remain low (10-30%) through midweek, they will increase slightly thereafter. Fire weather concerns remain low for now, but decreasing soil moisture will elevate these risks by the end of the week if beneficial rainfall remains scarce.

PRELIMINARY POINT TEMPS/POPS

Gadsden 71 92 69 93 / 10 0 0 10 Anniston 71 90 69 91 / 10 0 0 10 Birmingham 73 91 72 93 / 10 0 0 10 Tuscaloosa 75 94 73 96 / 20 10 0 10 Calera 73 92 72 93 / 20 0 0 10 Auburn 71 90 72 90 / 10 10 0 20 Montgomery 73 94 73 95 / 20 10 0 20 Troy 72 93 72 93 / 20 20 0 30

BMX WATCHES/WARNINGS/ADVISORIES

None.