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What to expect as a powerful winter storm wallops the U.S.
5m 28s
More than 70 million Americans are under winter weather alerts Sunday night as a fierce storm barrels across the country. At least six governors have declared states of emergency amid bitter cold and heavy snow. In the coming days, frigid temperatures are expected as far south as Florida. William Brangham speaks with MyRadar senior meteorologist Matthew Cappucci for more.