A powerful winter storm spread a paralyzing mix of heavy snow, sleet and freezing rain from the Ohio Valley and mid-South to New England on Sunday, compounded by bitter, Arctic cold gripping much of the US east of the Rockies. Winter storm warnings were posted for most of the eastern third of the United States covering 118 million people, as the deep freeze strained energy supplies in some areas, and the National Weather Service predicted widespread, prolonged travel disruptions. An estimated 157 million Americans were warned to bundle up against cold ranging from sub-zero temperatures along the Canadian border to below-freezing as far south as the Gulf of Mexico. The Arctic blast was accompanied by gusty conditions that sent wind-chill conditions a measure of how cold it feels based on the rate of heat loss from the body plunging as low as minus 50 degrees Fahrenheit in the northern Plains. Deep snow, thick ice Some of the heaviest snowfall, up to one foot or more since the storm developed on Friday, was mea...