Snow has begun in the Shoals just before 3am. Here are a few photos from Leighton/Tuscumbia.

A major winter storm southwest of the Tennessee Valley region drops several inches of snow in Louisiana and Mississippi through Sunday night before shifting northeast into Alabama early Monday.

Some isolated areas west of Jackson, Mississippi could see more than 4-5″ of total snowfall, but it’s very likely that the snowfall (and sleet/mix) potential fades enough to reduce the threat in Alabama and Southern Tennessee considerably.

Questions remain, though: as usual. Temperatures remain marginal for snow in this event, and models show a fairly wide range of total precipitation in this event. Even small changes in temperature profile and how heavy precipitation will be could dramatically change impacts across the Tennessee Valley. Forecast snow maps don’t show all the tiny changes that can make a big difference in the final result.

Here’s where our forecast stands as of Sunday evening:

Blue Counties: Northwest Alabama and Southern Tennessee

Clouds continue to fill in overnight as temperatures drop below freezing. A few flurries could begin as early as 1 AM. As more moisture streams in, snow showers begin in Northwest Alabama and Southern Tennessee around 3-6 AM. Rain and sleet may occasionally mix in with the snow through the morning. Accumulations are most likely in these locations, but are not guaranteed. There will likely be spots that do not see any snow accumulations. Any accumulations of snow would be a heavy, slushy snow, and would range from around 0.5″ to around 1.5″. Snow transitions to light rain in the afternoon and slowly tapers off by the late afternoon and evening. Some travel issues will be possible through the morning and early afternoon due to slushy spots on bridges and overpasses.

Pink Counties: North Central and Northeast Alabama

Light snow and/or rain/snow mix showers start as early as 5 AM. These get heavier through the morning. Cold rain, snow, and sleet are all possible through the morning hours. Some spotty, light accumulations of wintry precipitation are possible. Most of these accumulations would be very light, but a few spots could see up to 1″ of wintry mix accumulations. Wintry mix transitions to a cold rain in the afternoon. As temperatures drop in the evening, a bit of lingering rain could transition back to wintry mix in Northeast Alabama. Any wintry mix in the evening would be quite light and unlikely to lead to any significant accumulations. Some isolated travel issues will be possible through the morning and early afternoon due to slushy spots on bridges and overpasses.

Green Counties: East Central Alabama

Rain begins after 6 AM and continues off an on through the day. A few snowflakes or sleet pellets could mix in at times, but cold rain will be the predominant precipitation type. Accumulations of wintry precipitation is not expected.