The coldest air of the season is forecast to cover Minnesota into Thursday, and that has prompted the Rochester School District to cancel classes on Wednesday.

The announcement came late in the afternoon after school officials reviewed the latest weather forecasts. The National Weather Service has put the entire state under wind chill warnings. Forecasters are predicting lows in the teens below zero in the Rochester area Wednesday morning, while the mercury could approach -30 in parts of northern Minnesota.

The arctic airmass will be accompanied by gusty northwest winds that are predicted to produce wind chill readings as cold as -45 in southeastern Minnesota.