CHICAGO -- A Wind Chill Advisory is in effect until noon Friday with dangerous wind chills between -20 to -30 degrees.
A weak clipper low pressure system tracks south and east of our area giving a burst of light snow in the late afternoon and evening hours with an inch or less accumulation possible.
Bitterly cold wind chills are expected Friday morning with daytime highs in the lower single digits and sub zero wind chills continuing through the afternoon.
Several schools across the Chicago area are closed or opening late due to the dangerously cold conditions.
During the severe cold, Metra plans to place speed restrictions on all its lines.
Trains will be reduced to 65 miles per hour from 79 miles per hour. But temperatures lower than -10 degrees, the top speed will be reduced to 60 miles per hour. Conductors also plan to slow approaches into stations to prevent wear and tear on the braking systems and wheels. Crews have worked to remove ice from stations and rail yards. Snow and ice can also block and freeze a switch and prevent it from working so Metra uses heaters and shields to protect switches during winter weather. Hot jet blowers are also used to help clear the yards of snow and ice.
Even if all goes as planned, these additional steps can set off a domino effect causing trains to run behind schedule. Metra advisers riders to check train schedules and allow for extra time.
FRIENDLY REMINDER: Frostbite possible within 30 minutes to exposed skin. If you need to head out, be sure to dress appropriately.