"Few people can remember a blizzard fierce enough to shut down so many Interstate highways in so many states — all at once," reports CBS News correspondent Lee Cowan.
"They're pretty bad, they're really vicious. The ice is really thick with fresh snow on top. You can barely see. The visibility is horrible," said stranded motorist Nikki Wagner.
The storm closed parts of I-70 in Kansas, I-80 in Nebraska, I-90 in South Dakota and I-94 in Minnesota, among others.
"Several times the trailer changes lanes from right to left, just in a gust of wind," trucker Dean Zank told CBS station WCCO-TV.
Five deaths were blamed on slippery roads in Minnesota, South Dakota, Nebraska and Kansas. A sixth person was killed when a tornado hurled a car in Arkansas.
Travelers trying to get home after Thanksgiving were stranded in hotels across the Plains, but those who made it back safely weren't necessarily hunkered down at home. Wind, snow and ice snapped electrical lines and knocked out power to much of the eastern parts of the Dakotas.
More than 400 miles of eastbound Interstate 70 was closed, from Denver to Salina, Kan., with no word on when it might reopen. Westbound lanes were open in some areas.
"We're just waiting," said Corey Dagner, who was stuck in Limon, Colo., on his way home to Illinois after attending a wedding at the Breckenridge ski resort. "Nobody's sure what's going on and what time they're going to open the interstate."
The Colorado portion of I-70 was dry Monday, but the highway was impassable in western and central Kansas because visibility was nearly zero. Colorado halted eastbound traffic because there are so few places to stop and wait on the state's sparsely populated eastern plains.
But Colorado State Patrol spokesman Eric Wynn said the highway would be reopening Tuesday morning.
"Since the storm has moved on east, it's given our Colorado Department of Transportation time to get the roads cleaned, and our agency, the State Patrol, to assist all the motorists and get some of those vehicles that were off on the side of the road towed and going again," Wynn told CBS Radio News.
But another storm, which dumped 6 to 10 inches of snow in the California Sierra, could be moving in to the Plains, warns CBS News Meteorologist George Cullen.
"The snow will be spreading across the Rockies by this evening and probably another round of some snow, it may not be as heavy as what we just saw, but at least a few more inches of snow across the Great Plains (is likely)," Cullen forecast. "That wouldn't be until Wednesday night into Thursday."