Cold weather will get a shot in the arm next week. A new bitter air mass has formed far to the north, and it will be rushing southward through the heart of Canada Sunday and Monday. Expect the cold to reach the northern Plains and Upper Midwest Tuesday, then invade the eastern part of the United States during the middle of next week.

This will be an extremely cold arctic outbreak with temperatures averaging 10 to 15 degrees below normal across the Midwest, Ohio Valley and Northeast. That means a month that has already been very cold will turn out even colder.

Story by AccuWeather.com Senior Meteorologist John Kocet.