NWS warns of a severe winter storm with blizzard conditions across six states, threatening post-holiday travel.

A powerful winter storm driven by a rapidly intensifying cyclone was sweeping east from the Plains on Sunday, bringing heavy snow, ice, rain and severe weather expected to affect much of the country.

"An impactful storm system will move into Michigan Sunday into early next week, with accumulating snow, strong winds, and blowing snow," the National Weather Service in Grand Rapids said on Facebook. "The best chances for heavy snow will be across the Upper Peninsula, and the snow belts of lower Michigan.

High pressure will continue to promote dry weather across the Southeast. There will be at least some sunshine and it will be quite warm. Temperatures will be 10 to 20 degrees above average for this time of year.