Major thaw arrives Saturday; snow cover gone in a week?

That doorway to spring you see up ahead is called March.

But March is often a wildly variable month in Minnesota.

March is typically more winter than spring here. It’s our third snowiest month on average. The 30-year average for snow in March in the Twin Cities is 10.3 inches. That’s just behind January (12.2 inches) and December. (11.9 inches)

But first, we get an extra day of February. How lovely.

Mild March signal continues

I haven’t seen the weather maps for early March look like this since 2012. The upper-air forecast maps for the first two weeks of March look unseasonably mild. The cool fronts in the next two weeks still look to bring days with slightly above average temps, and the warm fronts appear ready to deliver the warmest air masses in over four months.

The predominant flow pattern aloft favors a strong push of mild Pacific air through the first half of March.

Highs surge into the 40s this weekend across much of Minnesota. Bank thermometers in the Twin Cities and southern Minnesota could flash higher than 45 degrees Sunday afternoon.

Highs above freezing are forecast for most of Minnesota starting Saturday through next week. Many of those days will be in the 40s.

Higher sun angle

March brings a higher sun angle and solar intensity to Minnesota. That extra energy is capable of greater snow melt potential.

With highs in the 40s and a stronger March sun, there may not be much snow left across much of southern Minnesota by late next week. There’s still deep snow up north, so the process will take longer. But expect to see your lawn emerging again around the Twin Cities next week.

Rain?

The medium-range maps still suggest the warmest push of air may come between March 7 and 14. And some models suggest a storm may arrive, with mostly rain during that week. Of course, this could change and feature more snow, but right now the system looks warm.

Rain is the most efficient way to take down snow cover in late winter.

Once we lose the snow across southern Minnesota, inbound air masses can easily be 10 degrees warmer than over snow-covered areas. There are 4 inches of snow at Minneapolis-St. Paul International Airport Friday morning.

Most of Iowa is snow-free.

Could we still get pounded with heavy wet snow later in March, or even April? Absolutely. But the pattern for the first two weeks of March overall looks unseasonably mild. I’ll keep the other eye out for the possibility of a March snow event lurking somewhere deep in the forecast maps.

Expect this next thaw to last a while.