Cancellations, delayed deliveries and outages

Over 5,000 flights are canceled within, into or out of the U.S. so far on Friday.

FedEx and UPS warned that customers could see delays on Christmas deliveries due to the weather's impact on major shipping hubs.

MORE: How to stay safe in cold as frigid temperatures hit

More than 1.1 million customers are without power in the U.S. and states of emergency have been declared from South Dakota to New York.

"This is really a very serious weather alert," President Joe Biden warned Thursday. "Please take this storm extremely seriously."

Danger on the roads

At least one person is dead from a 50-vehicle crash on the Ohio Turnpike, according to the Ohio State Highway Patrol.

State police, including in New York, Illinois and Michigan, are urging people to stay off the roads.

MORE: How to look out for neighbors, loved ones in extreme winter weather

The Michigan State Police said nine semi-tractor trailers crashed on Interstate 94 in Berrien County, where "visibility is near zero." A seven car pileup was reported in the same area, according to police.

"There are thousands of our first responders, emergency management personnel and utility crews out working in the elements to keep New Yorkers safe today," New York Gov. Kathy Hochul said in a statement Friday. "I'm asking everyone to stay off the roads this evening as conditions will worsen when temperatures drop across the state later today. Bundle up, stay indoors, and stay safe this weekend."