FXUS64 KBMX 080555 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 1255 AM CDT Sun Sep 8 2024 ...New AVIATION... .SHORT TERM... (Tonight through Monday) Issued at 907 PM CDT SAT SEP 7 2024 Our forecast from this afternoon remains on track as a cooler and drier airmass arrives from the north. No significant chances were necessary in the evening update. 87/Grantham Previous short-term discussion: (This evening through Sunday) Issued at 1225 PM CDT SAT SEP 7 2024 Our first true Autumn cold front of the season is currently headed south across the heart of Central Alabama. Northerly surface flow is being observed across the northern half of the state, as drier and cooler air advects southward. Winds are also becoming gusty behind the front, with some gusts above 20 knots showing up across far northern Alabama. As the front continues to move southward through the afternoon, dry air will also advect southward aloft greatly limiting development of shower activity. Although we can't completely rule out an isolated shower or two through the afternoon, confidence has lowered to the point of removing mention of PoPs for most of the area. Even the latest CAMs are backing off even further on development as of 1pm. A slight chance of a few showers will remain along and south of the I-85 corridor this afternoon where just enough moisture may hang on long enough, but will chances should come to an end by this evening. Previous low clouds that developed just ahead of the cold front are currently mixing out along the I-20 corridor, and clouds will continue to decrease through the afternoon. Winds will remain breezy through the afternoon behind the cold front, gusting above 20mph at times. High temperatures are still on track to top out in the mid 80s, while clouds will hang on across the far southeast counties to keep conditions a bit cooler. If you're headed out and about Sunday morning, you may have to break out your light jacket. Lows should be able to drop down into the lower 50s across the far northern counties and sheltered valleys, while mid to upper 50s and lower 60s are advertised elsewhere. Dry air will continue to advect southward during the day on Sunday, but will quickly be replaced by a more moist easterly surface flow across eastern and southeastern Alabama. As upper support quickly leaves the surface front behind, it is expected to stall across far southeast Alabama and return back to the west as a warm front. Some shower activity is expected along and south of I-85 as a result, and have kept slight chance of a shower mentioned across Pike, Bullock, Barbour, and Russell counties Sunday afternoon. Highs should top out in the low to mid 80s under mostly sunny to partly cloudy skies. 56/GDG && .LONG TERM... (Sunday night through next Friday) Issued at 330 PM CDT SAT SEP 7 2024 Latest model trends show a stronger low pressure system in the western Gulf by mid week, that moves northward into the Lower Mississippi Valley. This would lead to increased rain chances for Thursday and Friday across Central Alabama. Trended pops up, but will wait for consistency for making more significant changes. 14 Previous long-term discussion: (Sunday night through next Friday) Issued at 310 AM CDT SAT SEP 7 2024 An expansive area of high pressure will be situated near the Ohio Valley Monday morning, extending a footprint across a good portion of the eastern CONUS. This anticyclone will gradually move east into Tuesday as a preceding upper-level trough departs the East Coast. We'll remain fairly calm across Central Alabama this time frame with dewpoints in the 50s in our northern zones, increasing to the 60s across the south where only a passing shower or storm will is forecast across the southern portion of the low-level ridge. Highs in the 80s are forecast each day. Meanwhile, an antecedent area of low pressure is progged to be meandering across the western Gulf of Mexico, surrounded by an area of tropical PWs, well above 2.0". Medium range guidance brings the system back to the northeast toward the northern Gulf of Mexico, and eventually, the Lower Mississippi Valley Wednesday and into Thursday. Despite some uncertainty regarding the organization & evolution of this low, anomalous moisture values and forcing considerations led to increasing PoPs mid to late week. These would see further increases should latest model solutions remain consistent with the system continuing toward the Tennessee Valley. 40/Sizemore && .AVIATION... (06Z TAFS) Issued at 1253 AM CDT SUN SEP 8 2024 VFR conditions will persist through the TAF period. Winds will range from 5 to 9 knots from the north or northeast in the afternoon. Calm winds again after 02z. 16 && .FIRE WEATHER... A cold front will continue to push southward this evening, with northerly winds bringing drier air to the area. Northerly 20 ft winds at 5-12 mph tonight will become northeasterly to easterly Sunday at 5-10 mph. Minimum RH values will fall below 25 percent across far northwest Central Alabama for a few hours Sunday afternoon. Monday, minimum RH values will be above 35 percent areawide. Any rain chances will be confined to far southeastern Central Alabama. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 83 57 86 58 / 0 0 0 0 Anniston 84 59 86 61 / 0 0 0 0 Birmingham 84 62 87 63 / 0 0 0 0 Tuscaloosa 84 61 88 65 / 0 0 0 0 Calera 84 62 87 65 / 0 0 0 0 Auburn 83 64 84 64 / 10 10 10 0 Montgomery 87 65 87 66 / 10 10 10 10 Troy 85 64 83 66 / 20 10 20 10 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...87 LONG TERM....14 AVIATION...16