The National Weather Service has declared that dozens of counties in the region – at least two thirds of North Dakota and approximately the entire northern half of Minnesota – will be in an extreme cold warning from 6 p.m. Saturday, Jan. 18, through noon Tuesday, Jan. 21.

The 7 a.m. wind chill values were in the 30s and 40s below zero throughout Minnesota, including -35 in the Twin Cities. When you zoom out to see more of Minnesota and the entire region, it reveals the expansive area of Siberian air that has been spun south by a stretching polar vortex.