Chicago Weather Forecast: Ice Storm Warning Across Chicago Area

CHICAGO (CBS) -- An Ice Storm Warning is in effect across the Chicago area until 9 a.m. The entire area is also under a Winter Weather Advisory through 9 a.m. Tuesday.

Up to a half inch of ice had accumulated at airports in Aurora as well as at Chicago O'Hare and Midway, according to the National Weather Service.

Counties affected include Cook, DuPage, Will, LaSalle, Grundy, Kenall, DeKalb, and Kane in Illinois and Lake and Porter counties in Indiana.

Hazardous conditions will slow Tuesday's morning commute.

Strong winds will also develop into the afternoon and increase the threat of power outages later into the day and into the night, according to the National Weather Service Chicago.