Area Forecast Discussion
Issued by NWS Birmingham, AL
Issued by NWS Birmingham, AL
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458 FXUS64 KBMX 240843 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 343 AM CDT Tue Sep 24 2024 ...New SHORT TERM, LONG TERM... .SHORT TERM... (Today through Wednesday) Issued at 342 AM CDT TUE SEP 24 2024 Currently, central Alabama is between two larger systems. The first is a cold front to our northwest. The second is Potential Tropical Cyclone 9 to our south. In between, southerly flow has strengthened and weak isentropic lift has developed. This allowed some isolated to scattered showers to develop and slide north through the central sections of the area this morning. This will exit by midday, as the front begins to enter the area. Rain chances will be on the increase across the northwest through the afternoon and then will spread south and east through the evening. Showers and storms will be possible across the area. The best chance at seeing a strong to conditionally severe storm will be in the northwest. Questions in regard to the exact timing of the best coverage will keep the mention out of the HWO this morning. As we move into Wednesday, the front will stall out across the area and eventually slide back to the west. At the same time additional moisture from the southerly flow will manifest scattered to possibly widespread showers and storms across the area, especially in the afternoon. We will also continue to monitor the tropics to update any products throughout the next 2 to 3 days. 16&& .LONG TERM... (Wednesday night through next Monday) Issued at 342 AM CDT TUE SEP 24 2024 The main focus for the extended period is the potential tropical cyclone in the Gulf of Mexico. Guidance has been consistent in showing the larger-scale upper trough developing into a cutoff low over the Mid-MS Valley Wednesday night into early Thursday. As this takes place, the potential tropical cyclone is forecast to be intensifying prior to landfall in Florida. The tropical system is then expected to interact with the cut-off upper low and we start to see the Fujiwara effect take place with the tropical system and cut-off low rotating around each other before the tropical low becomes absorbed in the broader trough sometime Friday night into Saturday. Impacts: Flooding: Two separate features will lead to at least 2 distinct areas of flooding potential. First, the stalled frontal boundary/moisture convergence discussed in the short term. Then, the banding on the northwest side of the tropical track that could set up in the eastern and southeastern portions of Central AL Thursday. The placement of this axis of heavy rain will greatly depend on the eventual track, so updates on this area will be needed in coming days. Wind: Winds will steadily increase through the day on Thursday as the system gets closer. The forward speed of this tropical system is a big concern as the stronger winds will tend to translate further inland with a faster-moving storm. Current forecasts have maximum wind gusts generally in the 30-40mph range for the eastern half of Central AL, and gusts of 20-30 in the western half. This could change depending on the eventual track and intensity. This is a quick-moving system and by Friday morning/early afternoon, the potential tropical cyclone has largely merged in with the the upper level low. We`ll still see some lingering rainfall on the backside of the low through Friday evening, but that diminishes by Friday night/Saturday morning, leaving lower rain chances across the area for the weekend. 25/Owen && .AVIATION... (06Z TAFS) Issued at 111 AM CDT TUE SEP 24 2024 VFR TAF forecast is expected for the next 18 hours. There is some isentropic lift that is trying to develop in the southeast. This potentially could evolve into some showers this morning into the afternoon across the southeast, but chances are way too low to include at this time. Winds during the afternoon will be generally SW between 5 and 8 kts except for MGM which may be more southerly. Shower activity will approach from the NW on Tue ahead of a front. Went ahead and added in Prob30 starting at TCL after 22z and BHM after 00z. Will leave out of MGM for this cycle. 16 && .FIRE WEATHER... Increasing rain chances expected today through Thursday as a frontal boundary moves into the region and stalls. Min RHs may drop into the 40% range today ahead of the frontal boundary, but tropical moisture begins to build in ahead of the potential tropical cyclone Wednesday 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 90 68 79 64 / 20 60 90 70 Anniston 90 69 79 67 / 20 60 90 80 Birmingham 91 69 78 66 / 20 60 90 70 Tuscaloosa 91 69 79 66 / 30 60 80 60 Calera 91 69 81 68 / 20 60 90 70 Auburn 90 71 81 69 / 20 40 80 80 Montgomery 93 71 82 69 / 20 40 80 80 Troy 91 69 83 68 / 20 40 80 80 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...16 LONG TERM....25/Owen AVIATION...16