Area Forecast Discussion
Issued by NWS Birmingham, AL
Issued by NWS Birmingham, AL
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266 FXUS64 KBMX 251153 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 653 AM CDT Wed Sep 25 2024 ...New AVIATION... .SHORT TERM... (Today through Thursday) Issued at 337 AM CDT WED SEP 25 2024 A pre-frontal trough is currently moving toward I-65 this morning with a cold front nearing the Alabama line from the northwest. Rainfall has decreased a touch along the first boundary, but additional showers and storms have developed in Mississippi ahead of the front and will sweep through the area this morning. This area will likely expand into the southeast during the afternoon ahead of the boundary. There is a small chance of seeing a severe storm or two with damaging winds and a brief tornado possible through the afternoon. As we move through tonight, we will see the influx of moisture from the outer stretch of Helene. This will increase shower activity in the east and spread northward through the night. Showers will continue through the night and into the day Thursday, well ahead of the center of the storm. We will see some substantially high rainfall totals across the east well ahead of the storm. Localized flooding may occur in the east. Therefore, a flash flood watch is in effect. The center of Helene is forecast to arrive onshore around sunset Thursday night. Current forecast keeps the area on the west edge of the storm, so tornadoes should not be an issue. With the current track, our tropical wind gusts have increased and we now have a 30 to 40 percent chance at seeing tropical force winds in the southeastern area. If these numbers increase with the next update or two, we will have to consider a tropical storm watch for a few counties. At minimum a wind advisory will be needed overnight Thursday night into Friday morning, but still too early for that. The biggest impact through Friday morning will be the copious amounts of rain in the east. If you live in flood prone areas in the east, you need to make plans now on what you need to do. 16 && .LONG TERM... (Friday through next Tuesday) Issued at 337 AM CDT WED SEP 25 2024 Helene is expected to weaken to a tropical depression by Friday morning and then quickly becomes absorbed into the larger-scale cut- off low by Friday evening. There will be some wrap-around rainfall across the northern half of Central AL during the day on Friday before dry air gets wrapped in, decreasing the footprint of rainfall around the cut-off low Saturday through Sunday. This cut-off low persists over the region through at least Monday before shifting to our east Monday night into Tuesday. I won`t completely rule out some lingering shower activity under the closed upper level low over the weekend, but most guidance keeps the area rain-free, so my confidence to mention any rain chances is too low right now, but it`s something we`ll need to watch for in the next few days. 25/Owen && .AVIATION... (12Z TAFS) Issued at 646 AM CDT WED SEP 25 2024 A slow-moving pre-frontal trough will continue to move slowly southeastward today. Highest rain probabilities will be across TCL/BHM/EET/ANB/ASN through the morning, shifting to MGM/ANB by the afternoon. MVFR cigs are also expected to develop late morning and may temporarily drop to IFR. Winds will be light through the morning, becoming northeasterly to easterly at 4 to 7 kts after 15z. Even lower ceilings are expected late in the period but focused on the short term lines to keep the TAF from being to verbose. 16 && .FIRE WEATHER... Increasing rain chances expected today through Thursday as a frontal boundary stalls across the area. Tropical moisture builds into the area ahead of the potential tropical cyclone today through Friday keeping Min RHs 60-70%+. Winds increase substantially on Thursday as the tropical system approaches. Gusts could exceed 30mph in the eastern half of Central AL. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 78 66 73 62 / 80 70 90 90 Anniston 78 67 75 65 / 80 80 100 90 Birmingham 78 66 74 64 / 80 60 80 80 Tuscaloosa 78 65 78 64 / 80 40 60 60 Calera 79 67 76 65 / 70 60 80 80 Auburn 80 70 76 65 / 90 90 100 90 Montgomery 84 70 76 65 / 90 90 90 80 Troy 82 70 74 64 / 90 90 100 80 && .BMX WATCHES/WARNINGS/ADVISORIES... Flood Watch from 1 PM CDT this afternoon through Friday morning for the following counties: Barbour-Bullock-Calhoun-Chambers- Cherokee-Clay-Cleburne-Coosa-Elmore-Etowah-Lee-Macon-Montgomery- Pike-Randolph-Russell-St. Clair-Talladega-Tallapoosa. && $$ SHORT TERM...16 LONG TERM....25 AVIATION...16