Updraft® - Minnesota Weather News

Post-Christmas snowstorm potential; Arctic New Year?

Our docile December appears ready to go out with a wintry roar.

Weather maps in the next week to 10-days continue to suggest a powerful post-Christmas storm with heavy rain and snow potential for the Upper Midwest. And the latest forecast model twist suggests the season's coldest shot of Arctic air will pour south behind the system in the last days of December.

The good weather news? Pre-Christmas travel conditions look mostly favorable across the Upper Midwest. Riding over the river and through the woods to grandmother's house should be (mostly) hassle-free. Getting home may be a wintry challenge.

Here's the latest rundown on the weather scenario for the rest of 2018.

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Skaters on Lake Minnetonka in December 2012.

Sketchy ice 

Our extended December thaw has done a number on ice condition in Minnesota. My weather spies on Lake Minnetonka report only about 5-inches of ice thickness before last weekend. A solid week above freezing has made ice unstable in many spots. Be smart out there.

Light wintry mix overnight

Our inbound cool front brings a light mix of rain, ice and snow showers across Minnesota into early Thursday. Here's NOAA's NAM 3-km resolution model. Keep an eye out for potential light icing Thursday morning.

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NOAA NAM 3 km model via tropical tidbits.

Cool front

Thursday's front is more cool than cold. Temperatures dive about 10-degrees but remain above average into the weekend.

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NOAA forecast temperatures for Minneapolis via Weather Bell.

These forecast numbers for Duluth are typical for most of northern Minnesota.

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NOAA forecast temperatures for Duluth via Weather Bell.

Post-Christmas snowstorm potential 

The weather maps look potentially intense starting on December 26. All major models now drive a potent low-pressure storm into the Upper Midwest the day after Christmas.

The latest trends suggest a colder, more southerly track. That would mean mostly snow across most of Minnesota including the Twin Cities. With deep moisture and strong atmospheric dynamics, this system has the potential for heavy snow. I won't speculate on inches a week before an inbound storm, but if the models verify it could be a pile. If the system tracks further north again, precip may favor mostly rain.

This NOAA GFS run is typical of the latest model trends that bring heavy snow potential into Minnesota December 26-27.

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NOAA GFS model December 26-27 via tropical tidbits.

It will be interesting to watch how track and temperature trends change over the next week.

Arctic New Year?

The upper air pattern finally shows signs of bucking into a more wintry pattern in the last days of December. Northwest flow aloft should drive the coldest air so far this season into Minnesota.

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NOAA

The extended GFS 16-day temperature outlook favors a sub-zero air mass invasion. I'm skeptical we'll be able to get to the -25 temperature in today's guidance. But we're overdue for a sub-zero blast this season.

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NOAA GFS data for Minneapolis via Meteostar.

Keep in mind that guidance like this is more valuable with temperature trends rather than discrete temperature forecasts for any given day.

Bottom line? The odds for significant snow and cold are growing after Christmas. It's beginning to look a lot like winter as we move toward 2019.

Finally.