Over 2,600 flights have been canceled Monday, with airports in Denver, Dallas, Houston and Chicago hit the hardest, as a major winter storm unleashes heavy snow and ice across the South.
Up to 6 inches of snowfall has already buried parts of Oklahoma, Arkansas and Tennessee.
Major cities in the snowstorm's path for Monday include Little Rock, Arkansas; Memphis, Tennessee; and Nashville, Tennessee.
Near Houston, an 18-wheeler overturned due to ice on a freeway, shutting down traffic in both directions, according to Houston ABC station KTRK.
Schools will be closed Tuesday in Little Rock and Nashville due to the weather. Denver Public Schools also announced classes were canceled for Tuesday.
The snow will keep falling in the South throughout Monday, with an icy mix moving into southern Louisiana, Mississippi, Alabama and Georgia at night. Drivers should be on the lookout for slick roads through Tuesday morning.
Meanwhile, the Heartland is seeing record-low temperatures, with wind chill alerts issued from the U.S.-Canada border in Montana to the Rio Grande in Texas along the U.S.-Mexico border.
All-time lows could be recorded Monday in Sioux City, Iowa; Kansas City, Missouri; Tulsa, Oklahoma; Austin, Texas; and Dallas.
MORE: How to stay safe and prepare for freezing temperaturesDuring the Republican presidential caucuses in Iowa Monday night, the wind chill -- what the temperature feels like -- is forecast to plunge to minus 25 degrees.
On Tuesday, temperatures will be in the teens and single digits for Texas, Arkansas and Louisiana.
MORE: How is the winter weather going to affect the Iowa Republican caucuses?In Chicago, the wind chill is forecast to drop to minus 23 degrees on Tuesday.
The record cold is forecast to linger over the next couple days from Nebraska to Texas to Mississippi.
Monday night into Tuesday, snow and ice is expected from Washington, D.C., to Philadelphia, New York City and Boston. Some areas could see 1 to 3 inches of snow.
Lake-effect snow is also pounding western New York.
Up to 27 inches of snow fell just south of Buffalo, New York, this weekend, with up to 1 foot of snow accumulating in the city.
The Buffalo Bills were set to host the Pittsburgh Steelers on Sunday, but the game was pushed to 4:30 p.m. Monday because Sunday's intense snowfall made driving nearly impossible.
On Monday morning, the Bills were still looking for volunteers to help shovel snow from the stadium.
Erie County Executive Mark Poloncarz warned that many seats may still be covered in snow by game time.
The heaviest snow is ending in Buffalo, but the National Weather Service has issued another winter storm watch for the city for Tuesday night into Thursday, with the possibility of 2 to 3 feet of snowfall.