Cold is the main weather story across Alabama on this late January Sunday afternoon…
Temperatures bottomed out in the lower to middle 30s behind our strong cold front. The mercury has stabilized and temperatures are rebelling just enough against the strong cold air advection to nudge readings a degree or two upward. Temperature values at 11 a.m. across the I-20 corridor ranged from 39F at Birmingham to 40F at Tuscaloosa and Anniston. It was 31F at Decatur under cloudy skies, the coldest Alabama reading.
Upstream, it was 31F at Memphis, 24F at Harrison, AR and 21F at Springfield, MO.
Skies cleared quickly this morning behind a strong cold front that is now all the way out of the state. A weak lobe of vorticity was brushing northeast Alabama, and the slightly cooler air aloft associated with this disturbance was resulting in some stratocumulus clouds. Radar shows a few light snow showers just brishing the northeast corner of the state with this system. I could not find any official report of this activity reaching the ground.
Winds are strong out of the northwest averaging some 10-20 mph and occasionally gusting to over 25 mph. This is producing wind chills in the 20s over a wide area. The wind chill at Decatur at 11 a.m. was 19F with a northwest wind gusting to 22 mph and an air temperature of 31F.
A Lake Wind Advisory remains in effect for all of North and Central Alabama until 6 p.m.
The winds will diminish tonight and under clear skies, the mercury will plummet. It should be freezing by dark in the Birmingham area, with an expected overnight low of 19F. Some of the normally colder locations could see 15F or colder. Get ready for a hard freeze overnight. Remember to protect pets, livestock, exposed pipes and automobile radiators. Check on friends, family members and neighbors that might not be aware of the threat.
Monday looks dry and cold with highs in the 40s. Some cloudiness will return Monday night as southern stream disturbances pass. There is some chance a few sprinkles or snow flurries could get shaken out of the atmosphere late Monday night or Tuesday. Timing and atmospheric thermal profile will determine the precipitation type, but in any case it should be of litle consequence.
We stay in the 40s on Tuesday. Tuesday night looks as cold as tonight with lows around 20F.
Then things may get interesting.
The morning run of the GFS develops a surface low along the Louisiana coast late on Wednesday. We would expect the cold airmass to be in place over the state. Temperatures probably only make the low 40s on Wednesday and fall back into the 30s during the evening over parts of North Alabama. With moisture riding up and over the cold airmass, we could see a mix of precipitation over the state. If it is cold enough, snow is possible. Or it could be a mix of snow and freezing rain. Or it could be a cold rain. It is just too early to be specific and this forecast is more conjecture based on a single model run. We continually caution against reading too much into a single run. We will see if this trend continues to persist in successive model output. But the overall cold pattern is supportive of such an idea.
We go back to a dry and cold pattern into the weekend, but the morning GFS presents the idea of a bigger surge of cold air by late in the weekend. Things could get interesting again by late Sunday into the following Monday if the GFS idea of moisture and cold combine over North Alabama. In fact, that is the best presentation of a potential winter storm so far in the model runs with this recent pattern. But, I caution, that is on the edge of voodoo land and it is hard to take the models specifically serious beyond five days, and really beyond what we can see happening with conventional observation tools. It is fun to surmise about however.
Suffice to say, it will continue to be an interesting two weeks here in Weather Office.
