A dangerous arctic blast will drive swiftly into the heart of the nation beginning Sunday, just as millions of people in the Midwest and Northeast had put a deadly snowstorm and wicked cold snap behind them.
"It's beyond nostril-hair-freezing weather," says Michelle Vanden Plas, 40, of St. Paul, Minn. "It's been horrible and it's going to be even worse. We won't be able to walk the dogs at all and we take them out in pretty much anything."
Sunday through Tuesday, a cold air mass from the north will chill two-thirds of the U.S., leaving parts of the Mid-Atlantic and Northeast with single-digit highs and cities such as Chicago and Minneapolis with temperatures of 20 to 30 degrees below zero. That's before factoring in the wind chill, which is expected to make sections of the north-central states feel as chilly as 50 to 60 degrees below zero by Sunday evening.
The storm could bring heavy snow to the Great Lakes and Ohio Valley and freezing rain from the Deep South, along the Appalachians into New England for the next couple of days, the National Weather Service says.
"It's about as harsh a three-day period as you'll ever see in some areas of the country," says Joe Bastardi, chief forecaster at WeatherBell, adding that it has been at least two decades since the country has seen an air mass this cold. "If you are out there, it's dangerous. Temperatures like these can freeze flesh in 10 minutes."
Blame it on a "polar vortex," as one meteorologist calls it, a counterclockwise-rotating pool of cold, dense air.
"It's just a large area of very cold air that comes down, forms over the North Pole or polar regions … usually stays in Canada, but this time it's going to come all the way into the eastern United States," said National Weather Service meteorologist Phillip Schumacher in Sioux Falls, South Dakota.
Sunday's National Football League playoff game between the Packers and San Francisco 49ers at Lambeau Field in Green Bay, Wis., could be among the coldest ever played, even besting the infamous 1967 Ice Bowl game against the Dallas Cowboys. The National Weather Service forecasts a daytime high of zero to 5 degrees, dropping to 25-below overnight with wind chills reaching minus-50. Kickoff is set for 4:40 p.m. ET. A wind chill warning goes into effect at 7. Medical experts suggest fans wear at least three layers and drink warm fluids.
Even in parts of the country used to seeing chilly temperatures, officials are warning residents to take precautions.
Minnesota called off school Monday for the entire state — the first such closing in 17 years.
"It gets cold in Minnesota, but we are talking about historic cold in the coming days," says Bruce Gordon, spokesman of the Minnesota Department of Public Safety. "We are telling people to check on friends and family and neighbors — anyone who might need some help."
The South will dip into temperatures rarely seen. By Monday morning, parts of Kentucky could be below zero — "definitely record-breaking," said weather service meteorologist Christine Wielgos in Paducah, Ky. And in Atlanta, Tuesday's high is expected to hover in the mid-20s.
In Maple Grove, Minn., Jenna Diem, 40, spent Saturday morning running errands and filling her car with gas.
"We are used to the cold, but this is supposed to be extreme," Diem says.
The homeless population is a major concern in cities across the country as temperatures are expected to stay below freezing for several days.
"People are fighting for survival, especially in these Code Blue nights" says Kevin Moran, executive director of New Visions Homeless Day Shelter in Camden, N.J., where temperatures were already in the low teens Saturday.
A Code Blue is declared when temperatures drop near or below 20 degrees, requiring each New Jersey municipality to provide warming centers for its residents.
"There is a significant need for more homeless shelters," Moran says. "These people are looking every possible place to lay their head. Often they will go to an emergency room just to sit in the waiting room to escape the elements."
Seamen's Church Institute, a safe haven for men and women of the sea in Newport, R.I., will remain open to help people manage the cold.
"Because of the extreme temperatures right on the wharf we decided to stay open 24 hours a day," says Michelle Duga, superintendent of the institute. "We provided a fresh pot of soup, coffee and warmth all day long to anyone who had nowhere to go.
Seamen's had dozens of people coming through that needed food, coats, mittens and hats for or a place to sleep.
"It's hard to count how many people, but it was a whole lot of soup," Duga says.
In other parts of the country:
In the South, several school systems in northern Alabama are delaying their start times early next week because of overnight low temperatures expected in the teens.
In St. Louis County, Mo., one school district canceled classes Friday after 20 of its buses wouldn't start, and 85 others didn't have working air brakes because of temperatures that hovered around zero at 6 a.m.
In North Carolina, three Appalachian Trail hikers were hospitalized Friday after being stranded overnight in the snow without shelter. Wind chills were near 20 degrees below zero and snow drifts were up to 2 feet high.
Contributing: Tom Pelissero, USA TODAY Sports; Associated Press