Tens of millions of Americans are bracing for a massive winter storm Sunday, which is forecast to bring the heaviest snowfall and coldest temperatures to parts of the country in over a decade. The polar vortex has already prompted states of emergency in the Plains,

A major, disruptive winter storm was sweeping across the central U.S. on Sunday, forecasters said, bringing with it a dreaded combination of snow, ice and plunging temperatures. The National Weather Service issued winter storm warnings from Kansas and Missouri — where blizzard conditions are expected — to New Jersey.