In Chicago, where the Bears take on the Green Bay Packers at Soldier Field, the temperature is expected to be in the upper teens by kickoff. The thermometer might reach the teens as the Steelers face the New York Jets in Pittsburgh.
Blame it on a Canadian clipper, a cold air mass pile-driving its way into the United States from the province of Alberta.
In some parts of New York state, organizers are canceling winter festivals and meteorologists are warning residents to stay inside.
Meanwhile, a rare snow has been piling up on the North Carolina beaches. Forecasters are warning residents along the rest of the East Coast to be prepared for even more snow from a strengthening system in the Atlantic.