


Area Forecast Discussion
Issued by NWS Birmingham, AL
Issued by NWS Birmingham, AL
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042 FXUS64 KBMX 180450 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 1150 PM CDT Sun Aug 17 2025 ...New SHORT TERM, LONG TERM, AVIATION... .KEY MESSAGES... Updated at 1143 PM CDT SUN AUG 17 2025 - Medium to high chances of heat indices reaching 105 degrees Monday through Wednesday for areas mainly along and west of I-65. && .SHORT TERM... (Tonight through Tuesday) Issued at 1143 PM CDT SUN AUG 17 2025 Monday, high pressure will remain the main story, with northeasterly flow prevailing between the high centered to the west and the low moving slowly along the western Atlantic. CAMs are really trying to bring in dry air with PW values less than the 75th percentile for this time of year. This would have a large influence on the amount of dry air throughout the atmospheric profile and storm development. A few other models are holding on to moisture remaining high, with PW values closer to the 75th and 90th percentile. Will hedge a little higher than the CAMs for moisture, as moisture has been overperforming the past week. Through the afternoon, isolated development is expected with instabilities meager with a couple thousand J/kg and lowered LI values (even accounting for higher moisture). DCAPE will be around 1100 J/kg, so any storms that can develop will have a chance for strong downburst winds. Highs will be in the mid to upper 90s, with higher values in the west closer to the center of the high pressure. With the anticipated moisture, heat indices will be in or close to the triple digits, with a few areas in the west seeing up to 105 degree values. This Advisory criteria may be more isolated, but with lows consistently in the low to mid 70s, the heat will allow for little breaks and recovery, thus more impacts. Tuesday will be much of the same scenario as Monday, with all models trying to show a decrease in moisture through the afternoon. How much and if any will depend on how closer Erin makes it to the east coast. Isolated diurnal convection is again possible, though chances will be a lot lower for much of the area, with lowered instabilities and LI values. Right now, leaning dry and have most of the area rain free, except for the far east. Heat will again be a concern with less cloud coverage, and heat indices could again be near or at triple digits through the afternoon. Heat Advisories are in place for areas west of I65 through Tuesday afternoon, covering the nighttime hours to account for the higher low temperatures that would add to the heat stress. 24 && .LONG TERM... (Tuesday night through next Sunday) Issued at 1143 PM CDT SUN AUG 17 2025 Wednesday will be a repeat of Tuesday, with a large influence from how close Erin moves along the coast. Northeasterly flow will increase moisture as the tropical cyclone creates an area of increased rain over the SE CONUS. Activity here could linger through the night. By Thursday, low level flow should shift to a more southwesterly to westerly direction as the high pressure continues to drift to the west, and a low pressure and trough develops over the northern Plains and begins to move east. Moisture will return with PW values returning to the 90th percentile or max values. Scattered activity will be possible each afternoon, increasing in coverage through the weekend as the trough should swing a boundary through the area. Temperatures on Wednesday will remain in the low to mid 90s, with heat indices approaching triple digits. By Thursday, there should be enough cloud cover and convection that temperatures will drop into the upper 80s and low 90s. This would drop heat indices to below triple digits in most places, which should continue through the weekend. 24 && .AVIATION... (06Z TAFS) Issued at 1143 PM CDT SUN AUG 17 2025 VFR conditions are expected to prevail through the TAF period, with a chance for MVFR visibilities from fog development briefly at a few TAF sites. Otherwise, isolated convection is expected to develop by late morning through the afternoon on Monday. However, left mention of showers or thunder out of each TAF due to low confidence on any activity moving over a TAF site. Will amend if needed. NOTE: AMD NOT SKED has been added at TCL until further notice due to comms issues. 24 && .FIRE WEATHER... Minimum RH values will generally be in the 40 to 55 percent range the next couple afternoons with showers and storms remaining isolated to widely scattered. 20ft winds will remain light. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 72 96 73 95 / 20 20 10 10 Anniston 72 94 73 93 / 20 20 10 20 Birmingham 74 95 75 95 / 20 20 10 10 Tuscaloosa 74 96 75 97 / 20 20 10 10 Calera 73 95 74 95 / 20 20 10 10 Auburn 73 93 73 92 / 10 20 0 20 Montgomery 73 96 74 95 / 20 20 0 10 Troy 72 93 73 93 / 10 10 0 10 && .BMX WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM CDT Tuesday for the following counties: Fayette-Greene-Lamar-Marion-Pickens-Sumter-Tuscaloosa-Walker. Heat Advisory from noon Monday to 8 PM CDT Tuesday for the following counties: Bibb-Blount-Chilton-Dallas-Hale-Jefferson- Marengo-Perry-Shelby-Winston. && $$ SHORT TERM...24 LONG TERM....24 AVIATION...24