Spring Fever Outbreak: 70s return after 6 months, frost eases in southern Minnesota

There are a precious few "perfect" weather days every year in Minnesota. In the eyes of many, Wednesday is one of those days.

Warm sunshine. Balmy southwest breezes.  Temps in the 70s for the first time in six months. No mosquitoes.

Does it get any better in Minnesota?

• 75 degrees quite possible in the Twin Cities Wednesday afternoon.

• October 11 - last time the metro hit 70 degrees (75 degrees on that day)

• April 13 - average date of the first 70 degree temp at Minneapolis-St. Paul International Airport.

The winter of our discontent fades (a little) further from our memory Wednesday. You will be forgiven if, while at the Twins game or another outdoor location Wednesday afternoon, you let out a primal scream to banish your inner winter demons once and for all and celebrate springtime and the return of 70 degree weather to Minnesota.

The warmth rides in with gusty southwest wind and low humidity in the afternoon. Great for the winter weary Minnesota soul, but also perfect for fanning flames of any wildfires that get going.

The biggest risk? southwest Minnesota and the Great Plains. Here's the heads up from the Sioux Falls, S.D., National Weather Service.

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Red flag warnings are flying for a good chunk of the Great Plains Wednesday. I dealt with numerous red flag conditions in my nine years forecasting in Arizona. I've noticed an increase in fire weather conditions the past decade in Minnesota and the Upper Midwest.

April showers Wednesday night

A band of (welcome?) April showers crosses Minnesota Wednesday evening as a weak cool front slides through after our warm breezy Wednesday.

Showers and a few thunderstorms slide through northern Minnesota during the afternoon hours and reach the Twin Cities metro later in the evening, probably after dark. Here's the view on a mild day with approaching showers from the Duluth NWS.

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A flash of lightning or clap of thunder is possible in the metro Wednesday night. Most of the rain will be light, and gone by Thursday morning.

The forecast stays mild with 60s through Saturday, but turns wetter with shower and thunderstorm chances increasing Friday and again Saturday.

Our milder week gives way to a weekend cool down, and a welcome chance of some soaking rains, especially for southeast Minnesota. Here's the view from the La Crosse, Wis., NWS.

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'Operation Spring Thaw' in progress

The warmer temps and rain is finally taking some of the deepest frost in decades out of the ground in southern Minnesota.

Here's the chart of soil temps from the University of Minnesota Waseca Agricultural Research Station. You can see soil temps now in the 40s and 50s down to 4 inch depth. Frost is now out all the way down to about 20 inch depth, where soil temps hover around 32 degrees and are warming steadily.

Further north there is still plenty of frost deep in the ground around Minnesota. You can track 6-inch soil temps here this spring.

It's interesting to note that the frost layer leaves the ground both from above and below. Warmer air and rain thaw the top of the frost layer, and warmer temps in several feet down warm from the bottom once the cold air of winter is removed from above.

As far as soils beneath our feet are concerned, spring in Minnesota arrives form both above and below.