Expires:No;;331161 FXUS64 KBMX 250548 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 1248 AM CDT Thu Apr 25 2024 ...New AVIATION... .SHORT TERM... (Tonight through Friday) Issued at 946 PM CDT WED APR 24 2024 A cold front was slowly moving southward across the area this evening. There were a few showers out ahead of the front and they have mostly dissipated. Do not expect any additional development overnight. The main concern overnight will be the potential of fog development. It appears there will be a zone between Birmingham and Montgomery where some fog may develop. Drier air is working into the area from the north and skies have decreased in cloud cover since sunset in many spots. The interface of the cooler low temperatures and slightly higher moisture may be enough for some development before sunrise. Mentioned patchy fog at this time and will monitor visibilities for anything lower. Partly to mostly cloudy and warm on Thursday with highs 75 to 85. 75 Previous short-term discussion: (This afternoon through Thursday) Issued at 1236 PM CDT WED APR 24 2024 A weak surface front has entered into northwest Alabama as we approach midday. Broken mid-level clouds between 7,000 and 10,000 feet associated with the front are currently present generally along and north of the I-85 corridor. The presence of the clouds are expected to temper the diurnal curve just a bit and lead to high temperatures in the mid to upper 70s, while full sunshine will send highs into the lower 80s for locations such as Troy and Eufaula this afternoon. In terms of the rain chances today, it appears that the high-res guidance from yesterday was a little too bullish in terms of the rain chances. The 12z KBMX sounding still contains an ample amount of dry air across the profile, which will continue to be a limiting factor in terms of convective development. I've continued the slight chance of showers and perhaps a storm across western counties in Central Alabama through the peak heating of the day as the surface front moves southward near the U.S. 80/I-85 corridor. Overnight tonight, mid-level clouds are expected to gradually clear in most locations. With the stalled surface boundary still in the vicinity, we could be looking at the chance for fog development as low-level moisture pools near and just south of the front. Patchy fog has been added to the forecast overnight for eastern and southeastern locations and nearby major lakes and stream basins. Temperatures will be allowed to drop into the upper 40s for northern counties north of the front, while upper 50s are expected in the far south. Upper level heights will begin to rise during the day on Thursday as a 500mb ridge develops over the southwestern Gulf of Mexico. A shortwave trough embedded within northwesterly flow aloft will move through the region, along with the surface front lifting northward as a warm front. At least isolated showers and storms will be possible during the peak heating of the day with warm temperatures expected in the low to mid 80s. 56/GDG && .LONG TERM... (Thursday night through next Tuesday) Issued at 311 PM CDT WED APR 24 2024 Continued the thinking of the previous forecast regarding potential for some coverage of showers/storms Thursday night mainly north of I- 20. Went above consensus for PoPs in that timeframe. Otherwise, highs in the 80s and lows in the upper 50s to low 60s will stay in place for several days. The thinking for Monday night remains largely the same with rain and possible thunderstorms chances mainly north of I-59/20. 12 Previous long-term discussion: (Thursday night through next Tuesday) Issued at 335 AM CDT WED APR 24 2024 An upper-level trough moving into the Southern Plains will induce southerly low-level flow as far east as Alabama on Thursday evening. A warm front extending from Northeast Oklahoma to West Alabama will accelerate northward with the onset of southerly flow. Beneath west- northwest 500 mb flow of 30-35 kts, increasing moisture and warm advection may trigger isolated or scattered showers and thunderstorms Thursday evening mainly north of I-20. Any such activity will shift to the northeast and out of our forecast area during the overnight hours. Two shortwave ejections will occur across the Plains and Midwest in the Friday through Sunday period while a ridge remains in control over the Southeast CONUS. Eventually the second trough in the Plains should progress eastward on Monday and Tuesday leading to increasing rain chances mainly north of I-59. 87/Grantham && .AVIATION... (06Z TAFS) Issued at 1227 AM CDT THU APR 25 2024 A weak front is slowly moving southward tonight, and currently stretches from near Anniston to Tuscaloosa. Patchy fog is possible south of the front, where moisture is slightly higher. Reduced vis to MVFR/IFR is possible for a few hours, with MGM being the most likely terminal to be impacted. Any fog lifts with sunrise, with winds remaining at or less than 5kt through the day. Isolated convection is possible Thursday afternoon, but chances at any terminal are too low to include at this time. 14 && .FIRE WEATHER... A weak front with just a few showers/storms moves through this evening. 20 ft winds will be westerly at 6 to 8 mph, with minimum RH values above 40 percent. Another chance of showers/storms exists Thursday afternoon, with an increase in coverage compared to Wednesday. 20 ft winds on Thursday will become easterly at 6 to 8 mph, with minimum RH values 30 to 35 in the northeast, and 35-45 percent, elsewhere. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 79 56 83 62 / 10 20 10 0 Anniston 80 58 82 62 / 10 20 10 0 Birmingham 81 61 83 63 / 20 20 10 0 Tuscaloosa 81 61 84 63 / 20 10 0 0 Calera 80 61 82 62 / 20 20 10 0 Auburn 80 62 82 63 / 20 10 10 0 Montgomery 84 61 85 63 / 20 10 0 0 Troy 83 60 85 63 / 20 10 0 0 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...75 LONG TERM....12 AVIATION...14