textproduct: NWS Birmingham

KEY MESSAGES

Issued at 238 PM CDT SUN SEP 6 2026

- Significant Heat Risk: Maximum afternoon heat indices will remain between 105-108 degrees through this afternoon. A heat advisory remains in effect until 8 PM this evening.

- Storms this Afternoon and Evening: There is a level 1 out of 5 risk for severe thunderstorms this afternoon into the evening across the southern half of Central Alabama. Primary hazards will include gusty winds of 40 to 60mph and localized heavy rainfall.

DISCUSSION

(This afternoon through Saturday) Issued at 238 PM CDT SUN SEP 6 2026

Scattered to numerous storms have developed this afternoon within a very unstable environment as temperatures have easily risen into the mid and upper 90s. The 12z KBMX RAOB this morning measured steeper lapse rates aloft than we had 24 hours ago, as mid to upper level flow has transitioned from easterly to mostly northerly with the upper ridge centered over the southern Plains. Storms will continue to develop this afternoon and evening ahead of a surface front that is currently moving southward from Tennessee and northern Georgia. Microburst-type wind gusts will be the primary hazard today, with DCAPE values between 900 and 1200 J/kg and PWATs between 1.9 and 2.1 inches. Localized gusts of 40 to 60mph are possible underneath collapsing updrafts that are able to mix with the drier air aloft. PoPs this afternoon were increased overall above NBM guidance and may have to be increased further before all is said and done through the evening hours due to additional storm development from outflow boundary collisions and intersections.

Dangerous heat will continue through the day today as heat indices rise as high as 109 degrees mainly along and west of I- 65. A Heat Advisory will remain in effect through this evening. Looking into the day on Monday, we'll have a slight drop in temperatures and dewpoints overall as surface flow becomes easterly. In addition, drier air aloft will advect in from the north and will limit convective potential across the northern half of the CWA, while scattered storms will remain in the forecast south of I-20. Surface dewpoints are forecast to mix tomorrow afternoon into the upper 60s to lower 70s which will help to keep heat indices mostly below Heat Advisory criteria. At this time, we've opted to not go with a heat advisory for Monday but heat indices will still rise between 100 and 105 for most locations tomorrow afternoon and highs ranging from the upper 90s west to near 90 in the east. The easterly surface flow is expected to strengthen by Monday afternoon as the pressure gradient tightens due to the surface ridge centered over the Appalachians. Wind gusts near 20mph wouldn't be out of the question, which will certainly provide some much needed heat relief for our eastern and northeastern counties.

The 500mb ridge is expected to amplify to near 598 decameters and build eastward by the middle of the upcoming week. The upper level height rises and drier air aloft will limit rain chances to mainly the I-85 corridor and points south both on Tuesday and Wednesday with easterly to southeasterly surface flow continuing. An upper level low is then advertised by global guidance to move westward over the northern Gulf by Wednesday and Thursday, which will help transport additional tropical moisture northward into the region. Diurnal shower and storm chances are expected to increase as a result with highs topping out in the low to mid 90s areawide. By the end of the week, an upper trough is advertised to dive southward toward the Great Lakes with a trough axis stretching southwest into the Ohio Valley. A surface cold front is advertised to move in our direction by Friday and Saturday, but current guidance would indicate a good chance that there wouldn't be enough upper support to make it as far south as Central Alabama. We'll see how those trends evolve over the next few days.

56/GDG

AVIATION

(18Z TAFS) Issued at 238 PM CDT SUN SEP 6 2026

The main aviation concern for this afternoon continues to be TSRA development, which will pose a risk for microburst-type wind gusts in addition to rapid reductions in visibility due to heavy rainfall. PROB30s remain in the forecast for all terminals, but amendments are likely as storms approach the vicinity. VFR conditions are expected through the remainder of the forecast period as storms diminish overnight and northerly winds this afternoon become calm or variable overnight. Easterly surface winds will develop during the day on Monday, and could become gusty at times through the afternoon.

56/GDG

FIRE WEATHER

Minimum RH values will generally remain above 40% into next week. Low to moderate (20 to 50%) chances of showers and storms will be present this weekend with the best chances in the south today. Low (10 to 30%) chances for showers and storms will be in the forecast daily next week. Fire weather concerns are currently low, but decreasing soil moisture will begin to raise these concerns by next week given a lack of forecast rainfall.

PRELIMINARY POINT TEMPS/POPS

Gadsden 72 92 70 91 / 20 10 0 10 Anniston 72 91 71 89 / 30 20 10 10 Birmingham 74 94 72 90 / 20 20 0 10 Tuscaloosa 74 98 74 93 / 20 20 10 10 Calera 73 95 72 91 / 20 30 10 10 Auburn 72 90 71 87 / 40 30 20 10 Montgomery 74 96 72 92 / 40 30 30 20 Troy 72 95 71 91 / 40 30 30 30

BMX WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 8 PM CDT this evening for the following counties: Autauga-Barbour-Bibb-Blount-Bullock-Calhoun-Chambers- Cherokee-Chilton-Clay-Cleburne-Coosa-Dallas-Elmore-Etowah- Fayette-Greene-Hale-Jefferson-Lamar-Lee-Lowndes-Macon-Marengo- Marion-Montgomery-Perry-Pickens-Pike-Randolph-Russell-Shelby-St. Clair-Sumter-Talladega-Tallapoosa-Tuscaloosa-Walker-Winston.