Area Forecast Discussion
Issued by NWS Birmingham, AL
Issued by NWS Birmingham, AL
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379 FXUS64 KBMX 150606 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 106 AM CDT Sun Sep 15 2024 ...New AVIATION... .SHORT TERM... (Tonight through Monday) Issued at 814 PM CDT SAT SEP 14 2024 A convergence zone in the lower levels remains aligned northwest to southeast. This axis was generally east of I-65 and north of I-22 early this evening. This zone was north of a surface front and weak low pressure south of Montgomery. The showers depicted on radar did not have excessive rain rates at the moment, but some locations were receiving .3-.6 inches of rain in the past hour. Precipitable Water values were still high ranging from near 2 inches northeast to 1.7 inches southwest. Low level winds are forecast to increase overnight out of the east and expect the rain to continue along the convergent axis. This axis will also drift back to the west. Even though instability and shear are much lower than the past few days, rain has soaked into the ground and lowered the flash flood guidance. If heavier rain can develop and move over the areas that received heavy rain, flooding may become a risk overnight. Therefore, will keep the Flash Flood Watch going overnight. Rain chances are handled well as is much of the forecast. Overnight lows will be slightly cooler than last night mainly between 65 and 70 degrees. More showers/storms on Sunday with the focus shifted to the west. Highs mainly in the 70s. 75 Previous short-term discussion: (This evening through Sunday) Issued at 210 PM CDT SAT SEP 14 2024 The wet pattern continues for the short term with a low pressure and associated boundary that will linger along the coast with moisture continuing to stream up and around it into C AL. In the upper levels, an upper low is still present across the SE US but will continue to slowly weaken through Sunday. Our end result will be that of more showers expected for tonight into Sunday. QPF amounts continue to be a little elevated for tonight (additional 0.25-1.25 inch), so I will keep the flood watch going through 12z Sunday. However, expected amounts for Sunday during the day look to start to taper down to around 0.25-0.75 inch. Will forgo expanding the watch at this time. With elevated pops and lots of cloud cover, our diurnal range will not be great with lows in the 60s tonight and highs in the 70s for Sunday. 08 && .LONG TERM... (Sunday night through next Friday) Issued at 344 PM CDT SAT SEP 14 2024 The remnant surface to 500 mb low associated with Francine, will continue to drift southwestward over Mississippi on Sunday night and Monday. In addition, models are indicating the potential for a subtropical or tropical system near the South Carolina coast. With our area in between both systems, the corridor of highest rain chances will gradually shift southwestward as a surface ridge axis moves in from the east. By Tuesday, a drier airmass to our north should wrap around the low over the Carolinas, putting an end to the possibility of rain across the forecast area, except across our far southern counties. The dry conditions should continue through Friday as northerly flow persists on the western side of a cutoff 500 mb trough. 87/Grantham && .AVIATION... (06Z TAFS) Issued at 105 AM CDT SUN SEP 15 2024 A band of showers remains oriented northwest to southeast through the area tonight, and expect a gradual increase in coverage. This convergence zone will slowly move westward overnight and tomorrow, with the greatest coverage of showers across western areas through Sunday evening. Easterly winds at 8-10kts will occasionally gust to 20kts, especially within heavier showers. Radar trends indicate low chances of thunder, and have limited TS to after 15Z Sunday. A mix of VFR and MVFR cigs to start the period will trend to MVFR and IFR by sunrise. Improvement to MVFR is expected after 15Z, with VFR cigs at most terminals by 06/00Z. NOTE: NIL TAF continues for KANB until further notice due to large comms issue and missing obs. 14 && .FIRE WEATHER... Rain showers and moist conditions will continue for much of the area on Sunday before gradually shifting toward our southern counties on Monday. 20 foot winds will be from the east at 6 to 10 mph. Dry conditions will make a return Tuesday into Wednesday. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 79 65 83 59 / 30 20 20 10 Anniston 79 66 83 62 / 30 20 20 10 Birmingham 77 67 82 64 / 60 30 20 10 Tuscaloosa 78 68 81 65 / 60 50 40 20 Calera 78 68 81 65 / 60 40 30 20 Auburn 77 67 80 64 / 40 30 30 20 Montgomery 79 68 79 67 / 50 50 40 20 Troy 78 68 78 65 / 60 50 40 30 && .BMX WATCHES/WARNINGS/ADVISORIES... Flood Watch until 7 AM CDT this morning for the following counties: Autauga-Barbour-Bibb-Blount-Bullock-Calhoun-Chambers- Cherokee-Chilton-Clay-Cleburne-Coosa-Elmore-Etowah-Fayette- Jefferson-Lamar-Lee-Lowndes-Macon-Marion-Montgomery-Pike- Randolph-Russell-Shelby-St. Clair-Talladega-Tallapoosa- Tuscaloosa-Walker-Winston. && $$ SHORT TERM...75 LONG TERM....87 AVIATION...14