Mild-mannered through the weekend; big storm potential next week

Sunshine and milder temperatures across much of Minnesota allowed de-icing chemicals to work, improving driving and walking conditions in much of the state on Christmas Day.

Temperatures in parts of western Minnesota — from Tracy, Morris and Granite Falls to Wheaton and Ortonville, and even way up north to Roseau — climbed into the 30s as the mild air continued its surge. The Twin Cities had an afternoon high temperature of 17 degrees.

Past Christmases certainly have run a thermal gamut. The Twin Cities’ coldest Christmas morning of record was 39 degrees below zero (1879) while the warmest afternoon was 51 degrees (1922). The record coldest maximum temperature was 9 below (1996). The average low and high for Christmas Day in the Twin Cities are 10 and 25 degrees, respectively.

Pleasant weekend

The weekend looks to be mostly drama-free, as well. Afternoon temperatures will be rather close to normal. The Twin Cities are likely to experience highs in the mid-20s on both days.

A weak Alberta Clipper will spread light snow across much of Minnesota on Sunday. Newer forecast model runs have widened the forecast snow swath but have decreased the forecast amounts for northern Minnesota, as the snow will be spread out more. Much of the state could pick up an inch or so of dry snow.

Colder Monday

Monday will turn colder again with highs in the single digits for the northern half of Minnesota, and teens in the south. The southwest corner of the state might barely reach the low 20s.

Winter storm likely next week

Our troublesome blizzard this past week was a very unusual storm. It formed in the Pacific Northwest and should not have been so potent by the time it arrived here. It deepened rapidly as it reached Minnesota, pulled in much moisture and dropped significant snow over a large area. And the tight pressure gradient on the back of the storm caused those blizzard winds.

Most of our larger storms with noteworthy snowfalls form over eastern Colorado where the airflow from across the Rocky Mountains can impart cyclonic spin to begin the cyclogenesis process that is winter storm development. Favorable upper air dynamics then continue the storm growth and usually push the storm center toward the northeast, as Gulf of Mexico moisture is drawn in. Minnesota is a rather long state from north to south, so often ends up being an easy target of these storms.

Forecast models have been indicating the likelihood of such a winter storm for the upcoming week. The initial low pressure center will form over eastern Colorado on Monday, then track northeast toward Iowa. Such a path would put Minnesota in the bullseye for a broad swath of double-digit snowfalls over the course of Tuesday through Wednesday. If that track turns out to be the case, then gusty winds and some drifting are likely from the northwest winds on the storm’s trailing edge on Wednesday.

Storm tracks for storms that won’t be forming for a few more days are highly uncertain, of course, so this is just a outlook of how next week could easily play out for at least parts of the state.