Monday is Columbus Day, a federal holiday. The following public services will be affected:
Schools: Chicago's public schools will be closed. Most parochial and suburban schools also will be closed.
Government offices: Federal, county and city offices will be closed.
Postal service: No regular mail delivery, but express mail will be delivered.
Courts: Federal, state and county courts will be closed, except for Cook County Central Bond Court.
Banks: Most will be closed.
Transit: CTA, Pace and Metra will run on weekday schedules.

This is what it looks like today, via Google Maps:

For more on Christopher Columbus, read this at American Thinker:
"Christopher Columbus: The Good, the Bad and the Ugly"
"Christopher Columbus: The Good, the Bad and the Ugly"