According to the National Weather Service, prolonged exposure to extreme cold can quickly lead to frostbite or hypothermia. Frostbite most often affects uncovered skin and extremities, like fingers, toes and ears. Hypothermia develops when the body loses heat more rapidly than it can produce it.

The blast of frigid temperatures follows days of snowy, icy conditions across much of the country. It's bringing the coldest air of the season so far to the Midwest and the Northeast. About 10 record lows are possible Thursday morning and 20 are likely Friday morning.

This is all due to an early season arctic blast of cold air descending from Canada south eventually impacting most of the eastern half of the country. This cold air mass will stay over the east through Tuesday. Morning temperatures will eventually warm up Wednesday morning and afternoon highs warm up Wednesday and Thursday.

A dramatic shift arrives Sunday. An Arctic cold front sweeps through early Sunday, plunging the region into some of the coldest air we’ve seen all season.Sunday: The Cold Front ArrivesHere’s where things get serious.