Millions brace for 'catastrophic' ice as 18 states declare emergency amid historic winter storm

A powerful winter storm is barreling across the United States, as federal officials warn that ice and snow pose a threat to millions of Americans.

Gov. Sarah Huckabee Sanders, R-Ark, declared a state of emergency and activated the National Guard. She said road crews have pre-treated roughly 90% of state highways ahead of the incoming storm.

"We’re continuing to encourage every Arkansan to stay off the roads and to really take this storm seriously," Sanders said Saturday on "Fox & Friends Weekend."

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"Mother Nature is not something you get to control, and so we’ve got to be very aware of our surroundings and what’s coming," she later added.

A state of emergency has been declared in at least 18 states so far, including New York, Kentucky, Georgia and Texas. The 2,300-mile-long storm is expected to bring snow, freezing rain and sleet.

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More than 190 million people are under some form of winter weather alert, marking the highest number of U.S. counties ever simultaneously under a Winter Storm Warning, FOX Weather reported.

"We certainly hope people can enjoy the fun parts of the snow, but also ask them to be really cautious as they’re getting out and not take unnecessary risks," added Sanders as the first signs of the storm began to hit her state.

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National Weather Service Director Ken Graham described the storm as reaching a "staggering amount of distance" and told Americans to be prepared on "Fox & Friends Weekend."

He warned that ice would likely be one of the most dangerous aspects of the storm and said, "It’s a catastrophic situation for certain areas."

Overnight, snow and ice triggered power outages in parts of the country. Graham said that even with strong power grids, damage to local lines and falling trees could leave some neighborhoods without electricity for days.

He warned people to use their generators correctly, noting that "people lose their lives" when they’re used incorrectly. Graham’s advice to Americans was to prepare now by stocking up on food, having safe secondary heat sources and checking on elderly neighbors.

President Donald Trump said the federal government is ready to respond to the storm, even as thousands of flights have been canceled.

Alongside an alert from the National Weather Service, Trump wrote on Truth Social, "I have been briefed on the Record Cold Wave and Historic Winter Storm that will be hitting much of the United States this weekend. The Trump Administration is coordinating with State and Local Officials. FEMA is fully prepared to respond. Stay Safe and Stay Warm! President DJT."

FOX Weather's Mike Rawlins contributed to this report.