In response to dangerously cold temperatures and severe wind chills, schools across Minnesota and western Wisconsin have announced class cancellations and delays for Tuesday. The National Weather Service has issued extreme cold warnings, predicting wind chills as low as -45 degrees. Residents are urged to take precautions against frostbite and to stay indoors whenever possible. As the region experiences some of the coldest air of the season, a gradual warm-up is expected by the weekend.