textproduct: NWS Birmingham

KEY MESSAGES

Updated at 1100 PM CST SAT DEC 13 2025

- Dangerously cold temperatures expected Sunday night through Monday morning, with minimum wind chill values from 6 degrees north to 15 degrees south. - A Cold Weather Advisory is effect from 6 PM Sunday through 7 AM Monday morning.

DISCUSSION

(Monday through next Sunday) Issued at 1100 PM CST SAT DEC 13 2025

An upper low was positioned over the Central Great Lakes with broad troughing over the Midwest and Western Ohio River Valley Region. An arctic front was moving southeast toward the Interstate 59 corridor before midnight. Showers with a stray thunderstorm or two at times was primarily affecting our south-central counties with lighter showers across our east-central counties. Surface winds were increasing from the northwest at 10-20 mph across our northwest counties as strong near 1040 mb surface high pressure was building across the Northern and Central Plains overnight.

Today.

The upper low will open into a deep trough as it move east of the Great Lakes Region and toward the Northeast while deep troughing will swing eastward over much of the Tennessee Valley Region. Strong 1040+ mb surface high pressure will dominate over the Central Plains and force the shallow arctic front further southeast, approaching the Interstate 85 corridor toward sunrise. Northwest winds will increase further from 12-24 mph with gusts to 30 mph at times while clouds will gradually decrease through the daytime hours. Strong cold air advection will result in temperatures struggling to rise during the day with an overall decreasing trend with readings near freezing far northwest by early afternoon while highs will briefly be in the low 50s during the morning hours Sunday before falling. The combination of winds with these temperatures will keep wind chill values in the 20s across the northern half of the area with readings in the 30s across the southwest and south-central counties and readings in the 40s across the far southeast.

Tonight.

Deep troughing will move further east over the Mid-Atlantic and Northeast Coast while a northwest flow persists over the area. Strong 1040 mb surface high pressure will migrate eastward towards the Southern Ohio River Valley overnight while the arctic front moves further southeast across the Central Florida Peninsula. With a gradually decreasing surface pressure gradient, expect surface winds to persist from the north with decreasing magnitude in the 6-12 mph range generally overnight. Clearing skies with strong cold air advection will result in low temperatures from the lower teens far northwest to near 20 far southeast. The combination of winds with these temperatures will create minimum wind chill values early Monday morning from near 6 degrees far northwest to readings around 50 degrees south. A Cold Weather Advisory remains in effect from 6 pm Sunday night through 7 am Monday morning as a result.

Monday through Tuesday.

A northwest flow pattern aloft will persist through Tuesday while surface high pressure becomes more elongated, extending from across the Central Appalachians southwest into the ArkLaTex region on Monday then extending from the Carolinas southwest across the Northern Gulf Coast on Tuesday. Fair skies and dry conditions will continue with high temperatures ranging from around 40 far northwest to the upper 40s southeast on Monday followed by lows from the upper teens northeast to the lower 20s elsewhere Tuesday morning with highs from around 50 far northwest to the mid 50s south Tuesday afternoon.

Wednesday through Sunday.

A more zonal flow pattern will become established aloft from mid to late week as surface high pressure remains to our east and southeast. A weakness in the ridging will develop during the day Wednesday across the Lower Mississippi River Valley as a potent trough moves east over the Northern Plains to over the Western Great Lakes while a Southern Stream trough moves over Northern Mexico and South Texas. Expect an increase in clouds across the western portion of the area through the day with isolated showers possible across the northwest and far western counties by afternoon. At least scattered showers are expected late Wednesday night through much of Thursday with the best chance across the northern half of the forecast area in association with a secondary slightly deeper trough that will move eastward over the North- Central Plains toward the Ohio River Valley during this time frame. A cold front looks to move eastward through the area Friday with dry conditions returning from Friday into Saturday. Another trough may dig southward over the Ohio and Tennessee Valley Regions over the weekend, resulting in the approach of a cold front from the northwest that may allow clouds to increase with some shower activity late Saturday into Sunday, however, confidence is low at this time due to pattern disagreement among the available guidance members at this range. Expect gradually moderating temperatures through mid to late week ahead of the surface front that may approach the area late next weekend.

05

AVIATION

(06Z TAFS) Issued at 1100 PM CST SAT DEC 13 2025

Low clouds with showers will affect portions of the eastern and southern terminals through early Sunday morning as an arctic front pushes into the area from the northwest. There will be a very small chance of an isolated thunderstorm near MGM and AUO between 06z and 12z. Any reduction in visibility during and behind the shower activity should be limited in duration with the increasing winds already entering the northwest portion of the CWA as of this writing. Expect low- level winds to increase from the northwest at 10-20 kt through the daytime hours Sunday. Shower activity will move southeast of the area before midday with VFR conditions returning by Sunday afternoon areawide.

05

FIRE WEATHER

Showers with a stray thunderstorm will move southeast through late this morning, affecting portions of the eastern and southern counties. An arctic front will move through the forecast area today, resulting in 20 foot winds from 10-20 mph and gusts up to 25 mph. Min RHs will fall into the 25-40% range by this afternoon with temperatures from around freezing far north to around 50 far southeast. Winds will gradually ease overnight into Monday while Relative Humidity values will persist in the 20-30% range, with highs in the 40s areawide. Dry conditions are forecast through midweek.

PRELIMINARY POINT TEMPS/POPS

Gadsden 26 35 14 43 / 60 0 0 0 Anniston 30 38 15 46 / 70 0 0 0 Birmingham 28 35 18 43 / 70 0 0 0 Tuscaloosa 30 38 17 45 / 70 0 0 0 Calera 30 38 16 47 / 80 0 0 0 Auburn 40 44 21 46 / 80 10 0 0 Montgomery 40 46 20 46 / 70 20 0 0 Troy 42 48 21 47 / 60 30 0 0

BMX WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory from 6 PM Sunday to 7 AM CST Monday for the following counties: Autauga-Barbour-Bibb-Blount-Bullock- Calhoun-Chambers-Cherokee-Chilton-Clay-Cleburne-Coosa-Dallas- Elmore-Etowah-Fayette-Greene-Hale-Jefferson-Lamar-Lee-Lowndes- Macon-Marengo-Marion-Montgomery-Perry-Pickens-Pike-Randolph- Russell-Shelby-St. Clair-Sumter-Talladega-Tallapoosa-Tuscaloosa- Walker-Winston.