CHICAGO (CBS) -- A Winter Storm Warning has now been issued for central Cook County, including Chicago, as well as for northern Cook County and Lake County, Illinois.
The Winter Storm Warning is in effect from 2 a.m. to noon Friday. Estimated snow totals have been revised up to 4 to 8 inches.
A Winter Weather Advisory has been issued from 3 a.m. to 10 a.m. Friday for southern Cook County and all of DuPage County Lake County, Indiana.
Lake effect snow will increase for areas near the lake Thursday night, and then expand to the southwest suburbs during the early morning hours on Friday. Snowfall amounts overnight through Friday morning will range from 2 to 5 inches, but some locations may see as much as 6 to 8 inches.
Where the heaviest lake effect snow bands set up, visibility will be greatly reduced due to the potential for snowfall rates of as much as 2 inches per hour.
The Chicago Department of Streets and Sanitation has dispatched snow plows to the city's main roads and DuSable Lake Shore Drive in advance of the snowstorm.
Lake effect snow continues through the morning rush-hour, then decreasing snow chances starting by midday. Mostly cloudy and breezy for Friday afternoon with highs in 20 degrees. Lows will be near zero degrees for Friday night, with wind chills as cold as -10 degrees.
It will be mostly sunny Saturday with highs in the low 20s. Partly cloudy on Sunday with highs in the low 30s. More snow is expected by the middle of next week.
TONIGHT: Lake effect snow likely, especially for Cook County and Lake County, Indiana. Low: 9°
FRIDAY: Lake effect snow likely in the morning, then mostly cloudy and breezy in the afternoon. High: 19°
SATURDAY: Mostly sunny and breezy. High: 23°
for more features.