Widespread flooding is reported across much of the area, with rainfall totals of from four to seven inches in the past 24 hours.
Since rain -- heavy at times -- will continue falling over much of the region through much of this morning, flooding is expected to grow worse in already saturated areas.
Public transportation in the city also felt the impact of the weekend's rains. Flooding near O'Hare caused the Chicago Transit Authority to suspend Blue Line rail service into the airport. The Blue Line was operating as far as the Rosemont station, where shuttle buses were used to transport passengers to and from O'Hare. That shuttle service continued into Saturday night.
The CTA also reported the Yellow Line service halted because of flooding along Niles Road, where shuttle buses were used to transport passengers. The Green Line was also a flooding casualty, with service from the South Side into the Loop ending at 35th Street.
(The Associated Press and the Sun-Times News Group contributed to this report).