Dangerously cold air descended on the Midwest and Plains on Sunday, as new snow brought whiteout conditions to some areas and freezing rain threatened to cancel more flights in the Northeast.
The arctic blast — expected to be the coldest in decades — is bringing below-zero temperatures to more than half of the continental U.S. through Monday and Tuesday.
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The coldest air was hitting the Dakotas and Minnesota, which clocked temperatures of 20 degrees below zero on Sunday. At its lowest, the wind chill in Minnesota was a numbing minus 50 in Flag Island.
"It's just a dangerous cold," National Weather Service meteorologist Butch Dye in Missouri said Sunday morning.
And as they brace for the bitter cold, Midwesterners also must dig out of another nasty snowstorm.
Five to 9 inches fell Sunday in the Chicago area, while a foot was dumped in the St. Louis area. Eight to 10 inches was expected to pile up in central Illinois, Indiana and Michigan throughout the day.