This weekend's storms will threaten havoc everywhere east of the Rockies with possible record cold, rain, snow and even tornadoes.
Even West Texas was receiving heavy flurries Saturday, with up to 6 inches near Amarillo, where vehicles struggled to gain traction on ice and packed snow.
In all, 55 million people in 24 states were facing winter storm watches, warnings and advisories Saturday.
Freezing rain and snow is falling or is expected to descend on a vast swath from the Northern Rockies to the Great Plains toward New England. Storms are to soak the Southeast and may produce a few tornadoes and hail affecting 10 million people on the Gulf Coast from Louisiana to Alabama, CNN meteorologist Michael Guy said.
The Northern Plains and surrounding states are expected to feel "the coldest outbreak of arctic air" since last winter, said another CNN meteorologist, Karen Maginnis. Wind-chill factors could become dangerous at minus-30 degrees in those plains.
The National Weather Service predicted
the storm "will produce a variety of hazardous weather as it moves from the lower Mississippi Valley towards the Great Lakes this weekend."
"A swath of wintry precipitation is forecast from the Plains to the Great Lakes and Mid-Atlantic on Saturday, while severe storms and heavy rain are possible in parts of the Gulf Coast into the mid-South," the service added.
More than half the country is to be whipsawed by a front moving up from the Gulf on Saturday and then by another down from Canada on Sunday, the service said.
A Saturday storm is expected to deliver rain and thunderstorms from the lower Mississippi Valley to the Northeast. That moisture is expected to translate to snow in the upper Great Lakes and the Northeast. On Sunday, that rain is projected to intensify to a heavy downfall over the Mid-Atlantic coast and southern New England, the service said.
Meanwhile, a Canadian cold front will drop over the Great Plains to the Gulf of Mexico by Sunday morning, the service projected.
"The system will produce snow over the Northern High Plains/Rockies to parts of the Upper Mississippi Valley that will move southward to the Central Rockies/Plains by Saturday evening," the service said.
Even the Northwest will be affected and could receive moderate to heavy rain along the coast and snow in the intermountain regions, forecasters say.