(CNN) — This is the definition of rare air.
The National Weather Service warned Sunday that much of the United States will see this week the coldest temperatures in almost 20 years as an arctic cold front descends on 140 million people.
“It’s a piece of the polar vortex that’s coming down. It’s the coldest air in North America and it will be ours here in the lower 48,” said CNN Meteorologist Alexandra Steele. “We are going to shatter records.”
Temperatures were expected to be 30 to 50 degrees below average in some places, flipping the usual script.
On Monday, for instance, forecasters expect the high in Anchorage, Alaska, to be 34 degrees Fahrenheit, while Atlanta — aka Hotlanta — may see a high of just 24.
By Wednesday, nearly half the nation will shudder in temperatures of zero or lower, forecasters said. Even the Deep South will endure single-digit or sub-zero temperatures.
And in addition to the cold, there will be heavy snow in the eastern Plains and Great Lakes, as much as a foot Sunday.
Sunday’s weather had a huge impact on travel, with close to 3,000 flights originating in or heading to the United States canceled, according to flight-tracking website flightaware.com.
John F. Kennedy International Airport in New York closed briefly after an incident involving a regional jet, Delta Flight 4100 from Toronto.
Port Authority spokesman Ron Marsico said the plane, carrying 32 passengers, skidded into a snow bank while turning onto a taxiway after landing safely. No injuries were reported. The aircraft was towed to the gate, the Federal Aviation Administration said.
Flight operations were suspended for about two hours.
Traveling to or through Chicago was causing many headaches.
There were arrival delays at O’Hare airport of more than one hour on average, and 1,200 cancellations of departing or arriving flights. At Midway airport, there were 160 cancellations.
Here’s what to expect across the country this week:
Midwestern snow and one freakishly cold game
Snow was falling across the Midwest. In Brownsburg, Indiana, more than 4 inches had fallen during the morning, said iReporter Bill Byrd.
“Most people are staying in their homes, and church services are canceled,” he told CNN.
Indianapolis Mayor Greg Ballard told residents to stay off the streets, especially after nightfall.
“It’s not just a snow event, it’s a cold event, and that’s what scares us,” he said.
Parents should keep any eye on their kids who might be out sledding into the evening hours — there is no school Monday — and check to make sure they don’t get frostbite.
In Wisconsin, a sold-out crowd more than 70,000 hardcore Green Bay Packers fans hoping to see their team get closer to the Super Bowl had their loyalty tested Sunday as they endured temperatures between 4 and 8 degrees. With the wind, the air could feel as cold as minus 15 degrees.
The Packers will offer free hand warmers, hot chocolate and coffee at the afternoon game, spokesman Aaron Popkey said.
Packers running back Eddie Lacy said he didn’t think there was much he could do to prepare for a game this cold.
“It’s definitely going to be a different experience,” he said Saturday, according to the team website. “It’s mind over matter.”
In Embarrass, Minnesota, residents wondered whether they might see their record-cold temperature of 64 below zero, set in 1996, snap like an icicle.
“I’ve got a thermometer from the weather service that goes to 100 below,” resident Roland Fowler told CNN affiliate KQDS. “If it gets that cold, I don’t want to be here.”
Despite the conditions in the Windy City, officials said Chicago Public Schools will open Monday, but students can take an excused absence if they can’t make it to school.
Charles Williams, the city’s commissioner of the department of streets and sanitation, said plows will clear main roads and the streets around schools first.
The city had 12 centers for residents to seek warmth, one of which was to stay open all night through Tuesday. Libraries and some other city facilities would also be open, said Evelyn Diaz, the city’s commissioner of the Department of Family and Support Services. Illinois Gov. Pat Quinn said 100 warming centers were open statewide.
In St. Louis, authorities used a reverse 911 system to call people who might need assistance. More than 80 didn’t answer, Mayor Francis Slay said, so police were going to check on them.
Slay also said that the city would close on Monday except for emergency personnel.
“We expect this to be a three-day event,” he said, adding that 80 snowplows would be used to keep primary roads passable.
The Deep South
The arctic blast threatens to sweep subzero lows as far south as Alabama and plunge much of the Deep South into the single digits.
Freezing rain is also possible along the Appalachians all the way up to New England over the next couple of days, the National Weather Service said.
Deadly conditions
The low temperatures and wind chill are a dangerous recipe for rapid frostbite or hypothermia.
“Exposed flesh can freeze in as little as five minutes with wind chills colder than 50 below,” the National Weather Service’s Twin Cities office in Minnesota said.
Over the past week, at least 13 people have died from weather-related conditions.
Eleven people died in road accidents — including one man crushed as he was moving street salt with a forklift.
One man in Wisconsin died of hypothermia. And an elderly woman with Alzheimer’s disease in New York state wandered away from her home and was found dead in the snow in a wooded area about 100 yards away.
Travel nightmares
As snow fell in Missouri, Interstate 44 in Webster County was closed because of an accident involving multiple tractor-trailers, according to the state’s Department of Transportation website. The highway was also closed in Greene County when a semi crashed as it headed west.
The bad weather was headed east.
Cities like Cincinnati; Lexington, Kentucky; Louisville, Kentucky; and Memphis saw temperatures crash Sunday, and precipitation could lead to dangerous, icy driving conditions.
Roads will worsen Sunday night in Atlanta; Birmingham, Alabama; and Knoxville, Tennessee, forecasters said.
FlightAware.com said 4,500 flights were called off on Friday and Saturday.
And the FAA reported lengthy delays at several large airports including Detroit Metro Airport, Philadelphia International, and LaGuardia in New York.
This, too, shall pass
If there’s any good news about the biting cold snap, it’s that much of it should be over for the Midwest by Wednesday, the National Weather Service said.
In the meantime, those in the western part of the country can skip all the fuss. Most of the West can expect relatively pleasant weather through Monday.
By Holly Yan and Steve Almasy, CNN’s Todd Borek, AnneClaire Stapleton, Julia Lull, Jareen Imam and Erica Fink contributed to this report.
