James Spann: Cold tonight, storms by Tuesday for Alabama

BLUE SKY: As expected, morning clouds have dissipated, and the sun is out in full force over the northern half of Alabama this afternoon, with temperatures mostly in the upper 40s and low 50s. Tonight will be clear and cold; most communities will see a low in the 25- to 29-degree range early tomorrow.
THE WEEKEND: Tomorrow will feature a sunny sky; after the sub-freezing start we rise into the mid 50s. Then clouds move in tomorrow night, and we will mention the chance of some scattered light rain Sunday morning. But a decent part of the day Sunday will be dry; the sky will be mostly cloudy, with a high in the 57- to 60-degree range.
NEXT WEEK: The sky will remain mostly cloudy Monday, with a chance of showers; the day will be mild with a high in the mid 60s. Then, a deep surface low will move toward the Great Lakes Tuesday with a trailing cold front down toward Little Rock and Shreveport at midday. That cold front will bring an organized band of rain and storms to Alabama Tuesday afternoon and Tuesday night.
It is simply too early to really assess the severe weather threat; at the moment, with the primary surface low and upper dynamics so far to the north, it looks like we will have a band of strong storms in here Tuesday night with a chance of strong straight-line winds. Instability values will be pretty marginal, but shear values will be high. These type systems in winter can be tricky to deal with; keep an eye on updates over the weekend and we can be much more specific. Rain amounts of one-half to 1 inch look likely.
Colder air blows in following the storms Wednesday through Friday; for now, we will continue with a dry forecast. Highs will be mostly in the 40s, with lows in the 20s.
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