Get ready for weather whiplash as temps could approach 40 this weekend

Mother Nature isn't as fickle as you might think.

Sure, Minnesotans may experience a little weather whiplash as we bounce from days of subzero cold to temperatures flirting with 40 this weekend.

But such a dramatic change doesn't surprise Kenny Blumenfeld, senior climatologist in the Minnesota Climate Office.

About half of the time when Minnesota experiences a major cold spell, temperatures then jump into the 30s and 40s, he said.

Blumenfeld can dig back in history and find plenty of examples.

Take Feb. 2, 1996, Groundhog Day. "After some record cold conditions, within a few days of that, we had thunderstorms and temperatures rebounding into the 40s and even some 50s," Blumenfeld said.

That was the day when Tower, Minn., set the state's all-time low temperature of 60 below, he added.

About a week later, Tower hit 48 degrees — above zero.

"So Minnesota's most deepest and most famous record-setting cold outbreak was followed by a warmup of 108 degrees," he added.

Minnesota experienced the same temperature Ping-Pong during the 2014 winter that became branded as the year of the polar vortex. Days of brutal, bitter cold were followed by temperatures that went into the 40s across much of Minnesota, Blumenfeld said.

Apparently there's a perfectly good explanation for the roller coaster temperature ride.

Take this week, for example, Blumenfeld said. A strong cold front passed through the region, delivering Canadian air that dove past the Ohio River Valley and into parts of the South. The cold front is connected to a larger weather system with winds from the south on its backside.

"Winds out of the north make it cold. Winds out of the south make it warm," he said. "We're in the mid-latitudes, and the air mass is changeable, especially in fall, winter and spring. We can go from cold to warm regularly. … That's one of the things that makes our climate so great — it changes."

Along with temperatures in the upper 30s, rain and freezing rain are forecast for Sunday night in the Twin Cities. By Monday, about an inch of snow may fall. The weekend's mild temperatures are expected to fall into the teens later in the week, with a high in the single digits predicted by Friday.

Always a silver lining

Deep dives into subzero temperatures aren't something many people embrace, he acknowledged. But the deep cold is healthy for the state's lakes, forests and ecosystems, he said.

"We've seen a lot fewer outbreaks like this recently, and it's good to know we can still do it," he said.

What's not clear is how the rest of the winter will play out, he said. "It will be interesting to see whether this cold episode was isolated or whether it will persist."

In April 2002, temperatures hit the 90s in central and southern Minnesota and then was covered in several inches of snow at the end of the month, Blumenfeld said.

"If we know anything about Minnesota, we know we're not going to plan our next week based on what's happening this week," he said.

And that might not be all so bad.

"The next time we plunge into a deep freeze and it makes you feel hopeless, just remember there's a pretty good chance within a week, it will almost as warm as it was cold," Blumenfeld said.

Mary Lynn Smith • 612-673-4788