Heavy snow, heavy ice and thunderstorms will move from the Rocky Mountains to the East Coast, creating dangerous travel conditions. Cities such as St. Louis, Indianapolis and Cincinnati could be hit the hardest by snow and ice, with snowfalls of 6 to 12 inches and ice accumulations of 0.25 to 5 inches. These conditions can cause tree branches to fall and power outages.

“A combination of wind gusts exceeding 35 mph and heavy snowfall may lead to blizzard conditions across the Central Plains through Sunday morning,” the weather service said on X. “Whiteout conditions make driving dangerous to impossible and increase the risk of getting stranded .”

Severe storms will rage across the South on Sunday and could affect seven million people from Southeast Texas to Mississippi and southern Tennessee.

“Dangerous sleet and freezing rain are expected across eastern Kansas and the Ozarks, extending east to the Ohio Valley,” the weather service said. “Icing is also expected in portions of the central Appalachians Sunday into Sunday night. Treacherous travel conditions are expected, with power outages expected in areas with more than a quarter of an inch of ice accumulation due to freezing rain.”

Monday will be a chaotic day across the Ohio Valley, Mid-Atlantic and Northeast as the storm hits Pittsburgh, Richmond, Washington DC, Baltimore and Philadelphia. The heaviest snowfall could affect the area south of New York City.

Behind this storm, arctic air will pour down from Canada and temperatures will be well below average from the northern Plains to the Southeast for much of next week.