One of the coldest Arctic outbreaks in 20 years is expected to plunge the Midwest into sub zero temperatures. The freezing cold will also spread to the east and south.
According to the Associated Press, the frigid temperatures are due to a "polar vortex."
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.