409 FXUS64 KBMX 080002 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 602 PM CST Thu Nov 7 2019 .UPDATED... Aviation Discussion. && .SHORT TERM... /Updated at 0252 PM CST Thu Nov 07 2019/ Through Friday. Cold front is finally making its way through north Alabama, and will pass through our area this evening. Rain associated with the front pretty much stopped its southward advancement earlier today. But additional showers started developing south of the front by early afternoon, and were starting to overspread most of our area by 3 pm. Will continue with the categorical POPs early on tonight, but models do continue to show dry air starting to move in quickly in the wake of the frontal passage. Thus, POPs quickly taper off to zero after midnight and before 6 am Friday. Strong cold advection sets up through the remainder of the day on Friday, with gusty north winds. /61/ .LONG TERM... /Updated at 0420 AM CST Thu Nov 07 2019/ Friday night through Sunday. Overnight temperatures will fall into the upper 20s to upper 30s, with freezing/subfreezing temperatures possible for the northwestern two-thirds of the area by early Saturday morning. A Freeze Watch will be issued for this area for Friday night into early Saturday morning. Temperatures at or below freezing are possible again overnight Saturday and into Sunday morning, but guidance trending warmer suggests reduced confidence in any one particular area outside of the typical sheltered/cool spots. Sheltered areas across the north would stand the best chance of frost at this time. Otherwise, airmass modification will help warm overall temperature ranges by the latter part of the weekend with highs in the low to upper 60s by Sunday afternoon, still just a few degrees below average. Monday through Wednesday. An upper-level pattern best characterized by persistent eastern CONUS troughing/negative height anomalies is expected to continue into next week, with continuance of a Rex Block appearing likely. This is suggested by the southern stream upper-level low near the northwestern coast of Mexico and positive height anomalies near the Pacific Northwest. Meanwhile, an upstream trough/disturbance in the Polar jet is advancing southeastward into the Northern Plains, carrying with it a distinct Arctic airmass at the surface. As this advances southeastward toward the Mississippi River Valley, another system is forecast to affect the area by Monday night. Rain chances/amounts will be heavily contingent on moisture availability ahead of the associated frontal boundary. (This isn't too dissimilar from the system affecting the area today as the mid/upper-level pattern is comparable). However, there are a lot of uncertainties with the evolution of this system this far out. Though very cold air is very likely to affect a large portion of the country (including Central Alabama), return flow ahead of the associated cold front is uncertain as there may be little residence time of favorable low-level wind trajectories over the western Gulf. Thus, moisture availability may be limited to sub-tropical jet considerations. Regardless, have kept PoPs truncated at generally ~30% or less until a few more details can be resolved from a forecast perspective, including any development/structure of a surface low along the front. Either way freezing temperatures collocating with precipitation appears unlikely, though can't be completely ruled out across the northwest Tuesday morning. No impacts are expected from any wintry mix at this time as amounts would be negligible, if they manage to happen at all. Thereafter, a widespread freeze is possible Tuesday night with temperatures at or below freezing reaching the AL/FL Gulf Coast. Lows in the 20s are possible across all of Central Alabama, with teens possible in our north & northwest counties. 40/Sizemore && .AVIATION... 00Z TAF Discussion. A cold front is moving southward through the area this evening, with northerly winds now at all terminals, except MGM and TOI. Winds will turn at these two terminals within a couple hours. A period of gusty winds is possible, with gusts up to 22-25kts possible for much of the overnight period. Additionally, a large area of rainfall will continue to move generally eastward across the area. South of the front, fog has brought visibilities down at MGM and TOI. These conditions will improve once rainfall arrives, at 01Z and 02Z, respectively. Rainfall could be heavy at times, reducing visibilities, but flight restrictions will mainly be a result of MVFR to IFR ceilings. As rainfall ends, low ceilings will remain. Believe models are a bit optimistic with improving sky conditions and will hang on to at least MVFR cigs until Friday mid morning. As skies do clear, northerly winds at 9-12kts are expected through the day Friday. 14 && .FIRE WEATHER... A strong cold front will move through the area through tonight, with accompanying showers. Drier, but windy conditions are expected by Friday as high pressure builds back into the region. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 38 51 30 57 34 / 80 0 0 0 0 Anniston 41 53 32 58 35 / 90 0 0 0 0 Birmingham 38 51 32 58 38 / 70 0 0 0 0 Tuscaloosa 39 52 32 60 37 / 60 0 0 0 0 Calera 40 53 33 59 36 / 80 0 0 0 0 Auburn 47 57 37 57 36 / 90 10 0 0 0 Montgomery 50 59 38 61 38 / 90 10 0 0 0 Troy 52 60 39 61 37 / 90 10 0 0 0 && .BMX WATCHES/WARNINGS/ADVISORIES/... Freeze Watch from Friday evening through Saturday morning for the following counties: Bibb...Blount...Calhoun...Cherokee... Clay...Cleburne...Etowah...Fayette...Greene...Hale...Jefferson... Lamar...Marengo...Marion...Perry...Pickens...Randolph...Shelby... St. Clair...Sumter...Talladega...Tuscaloosa...Walker...Winston. && $$