The weather warnings are dire: Life threatening wind chills. Historic cold outbreak.
Winter is normally cold, but starting Sunday tundra-like temperatures are poised to deliver a rare and potentially dangerous sledgehammer blow to much of the Midwest, driving temperatures so far below zero that records will shatter.
One reason? A "polar vortex," as one meteorologist calls it, which will send cold air piled up at the North Pole down to the U.S., funneling it as far south as the Gulf Coast.
The temperature predictions are startling: 25 below zero in Fargo, N.D., minus 31 in International Falls, Minn., and 15 below in Indianapolis and Chicago. At those temperatures, exposed skin can get frostbitten in minutes and hypothermia can quickly set in because wind chills could hit 50, 60 or even 70 below zero.
Temperature records will likely be broken during the short, yet forceful deep freeze that will begin in many places on Sunday and extend into early next week. That's thanks to a perfect combination of the jet stream, cold surface temperatures and the polar vortex - a counterclockwise-rotating pool of cold, dense air, said Ryan Maue, of Tallahassee, Fla., a meteorologist for Weather Bell.