A piece of the polar vortex spills into the Midwest, creating extreme cold for the Chicago area and northwest Indiana for the next few days. For Sunday morning, actual air temperatures will peak early and fall throughout the day.

Central Indiana once again had highs around 40° on Saturday. However, this was early, around 12-1 a.m., before a cold front passed through. Temperatures slowly fell with afternoon highs only in the 30s.

Americans face dangerously cold temperatures as a polar vortex brings life-threatening conditions. Nighttime lows may drop to minus 23°F in northern states, with impacts felt across the contiguous US,