Area Forecast Discussion
Issued by NWS Birmingham, AL
Issued by NWS Birmingham, AL
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261 FXUS64 KBMX 260047 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 747 PM CDT Tue Jun 25 2024 ...New SHORT TERM, AVIATION... .SHORT TERM... (Tonight through Thursday) Issued at 736 PM CDT TUE JUN 25 2024 A stationary front was located just south and west of central Alabama this evening. This front was a dividing line between drier air to the north and much more humid conditions to the west and south. The mid level ridging remains over central Alabama overnight with the moisture axis remaining close to where it is. Since dew points mixed into the 50s and 60s this afternoon, especially east, went ahead and lowered the overnight lows mainly east of I-65 as a large diurnal swing has been observed lately. Otherwise, the forecast looks good with the best rain chances entering late Wednesday into Thursday. 75 Previous short-term discussion: (This afternoon through Wednesday) Issued at 107 PM CDT TUE JUN 25 2024 The 700mb portion of the ridge is centered just west of Central Alabama this afternoon, and we have a very hot and dry airmass across the area. Dewpoints have mixed efficiently into the upper 50s to mid 60s which is resulting in RH ranging from 25 to 35 percent as temperatures have risen into the mid 90s. Based on the trends, we`re aiming for another afternoon of highs in the upper 90s with some triple digit readings certainly possible amidst sunny skies. Unfortunately, the miserable heat continues. Short term models have really come into better agreement this morning on a brief breakdown in the ridge tomorrow as a low to mid- level trough moves across the region. A complex of thunderstorms is progged to develop along a cold front over the Midwest tomorrow morning and quickly advance south into the Midsouth region. Strong outflow driven storms will move into northern Mississippi by midday with additional thunderstorms expected to develop across western portions of Central Alabama during the afternoon as moisture increases dramatically with the trough axis. In fact, PWATs will increase from ~1-1.25" in the morning up to ~2" by the afternoon. It appears that convection will spread eastward, but with decreasing intensity and coverage as we move into the later part of the day, so still expecting hot temperatures, especially for areas generally east of I-65. The evolution of this thunderstorm complex and related nearby convective development is difficult to pinpoint at the moment given the mesoscale variability in this summertime pattern, but could see some potential for strong winds in these storms, mainly west of I-65 where they will be mostly outflow driven. Although progged wind shear values are weak, if model trends continue to favor some cold-pool driven storms across our west, then a risk of severe storms with damaging wind potential may need to be advertised in the forecast. 86/Martin && .LONG TERM... (Wednesday night through next Monday) Issued at 229 PM CDT TUE JUN 25 2024 The breakdown of the upper ridge (or, its retrograde into the southwestern states) will be fairly brief. After the passage of the upper shortwave trough and associated convective system Wednesday night and Thursday, global models bring the upper ridge center back east of the Rockies from Friday through the remainder of the long term. This puts central Alabama back into a typical mesoscale diurnally driven summertime pattern. That means POPs of 40 to 60 percent on days where the ridge center is more in the southern plains, and 20 to 30 percent on days where the ridge center edges eastward into the southern Mississippi Valley and Southeast states. Unless we get more rain than expected in the short term, then ground conditions will continue to become increasingly dry enough to support daytime temperatures in the mid/upper 90s by this weekend into (at least) early next week. /61/ && .AVIATION... (00Z TAFS) Issued at 736 PM CDT TUE JUN 25 2024 VFR conditions are expected for central Alabama terminals. Some fog developed last night south, but the dry air has settled into the region with no precipitation today. Do not expect a repeat of this fog development at this time. PROB30 was mentioned for Wednesday afternoon as some showers and thunderstorms will develop. The best chances look to be west with chances extending beyond the period. Winds will stay on the light side with some west to southwest component at times. 75 && .FIRE WEATHER... Hot and dry conditions will continue through tonight. Moisture begins to increase from the west on Wednesday, but RH values in East Alabama will still drop into the 28 to 35 percent range. Chances for showers and storms will return from the west on Wednesday. Scattered, mainly afternoon and evening showers and storms are expected Thursday into the weekend, with the highest coverage in the southeast. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 65 99 69 93 / 0 20 50 50 Anniston 68 98 71 90 / 0 20 40 60 Birmingham 73 99 72 93 / 0 40 50 50 Tuscaloosa 73 96 71 91 / 0 60 60 50 Calera 69 98 72 93 / 0 40 50 60 Auburn 72 96 73 92 / 0 20 20 60 Montgomery 71 98 72 93 / 0 40 40 70 Troy 71 97 71 93 / 0 30 30 70 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...75 LONG TERM..../61/ AVIATION...75