Millions of Americans from the Plains to the East Coast faced the threat of blizzards, heavy snow, treacherous ice and freezing rain through Monday, the National Weather Service said on Saturday.
Governors in Kentucky and Virginia declared states of emergency ahead of the winter storm.
"The storm is still taking shape," meteorologist Rich Bann of the NWS's Weather Prediction Centre said Saturday evening. "But this thing has multiple hazards from heavy snows in the Plains to significant icing covering roads farther south."
He added that more than 60 million people in the US were affected by winter weather warnings, watches or advisories this weekend.
A swath extending eastward from Nebraska and Kansas through Ohio, Indiana, southwestern Pennsylvania and northwestern Virginia could see from 2.5 cm to 30 cm of snow. Ice could knock out power lines and cause widespread outages.
A wintry mess of freezing rain and ice will hit southern Missouri, Kentucky and Tennessee on Sunday, Bann said, likely making roads hazardous and downing power lines.
"It'll be nearly impossible to drive in some areas," he said.
The Kansas City International Airport in Missouri closed temporarily on Saturday afternoon due to rapid ice accumulation, officials said on social media.
Bann said that the storm should move past the East Coast and into the Atlantic Ocean by late on Monday, but a new blast of Arctic air will bring frigid cold to the eastern two-thirds of the US by the middle of next week.

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