Major winter storm targets Minnesota

A high-impact winter storm is heading northeast out of the Southern Plains toward Minnesota. Here is the nationwide picture of winter storm warnings:

Snow has been tracking across Nebraska and is advancing toward southwestern Minnesota early this Wednesday morning.

Snow will spread northeast across all of Minnesota on Wednesday. Travel conditions will deteriorate later in the day and Wednesday night.

Winter storm warnings have been posted for the northwestern two-thirds of Minnesota from Wednesday afternoon through Friday morning. Winter weather advisories for lesser amounts of snow and some mixed precipitation have been posted just south of the winter storm warnings area and do include central and northern parts of the Twin Cities metro area.

Rain in December

Warm, moist air from the south will change the snow over to rain Wednesday night in east-central and much of southern Minnesota. Rain will continue in those areas through the day on Thursday while more snow falls on the warned area to the northwest.

East-central to southeastern Minnesota could receive as much as around an inch of rain by Thursday night. The rain will melt snow that has fallen. In addition, rain and melted snow on frozen grounds might cause local flooding.

Twin Cities area

I expect snow to reach the Twin Cities area later Wednesday afternoon, become heavier during the evening and result in a quick burst of a few inches. The snow will change over to rain Wednesday night. Expect rain to continue on Thursday and into Thursday night.

Colder air on the back of the storm will change the rain back to snow later Thursday night. Snow will taper off and end on Friday. Metro snowcover at the end of the storm might be just an inch or two.

Expected snowfalls

Much of the northwestern two-thirds of Minnesota is likely to pick up somewhere around 6 to 12 inches of new snow. Locally higher amounts around 12 to 15 inches might fall, mainly in western Minnesota and on the slopes above the North Shore. Here's how it looks at this time:

Worst travel conditions

Two situations for difficult and dangerous travel are likely.

The first of these will develop across mainly open areas of western Minnesota for Thursday afternoon and night as snow continues to fall while the wind increases. Near-blizzard conditions are possible.

The other dangerous event will occur late Thursday night and Friday morning from the Twin Cities area to southern Minnesota when falling temperatures cause a flash freeze of the rain that had fallen. I expect the Friday morning commute in the Twin Cities to be icy and slow.

Arctic chill for Saturday

Canadian air behind the storm will make an afternoon mug of cocoa seem like a good idea. Minnesota likely will see high temperatures from the single digits just into the low teens.