One of the largest winter storms in decades hit the U.S. Midwest last night, pictured here on Feb. 1 stretching from the Rockies to the east coast. Sleet, snow and rain from the storm are now affecting at least 30 states. In fact, the ragged edges of the storm are spurring powerful thunderstorms along the Gulf Coast. Chicago endured blizzard conditions and thundersnow, along with half a meter of snow accumulation.

—David Biello