Saturday's storms brought traffic to a standstill on the Edens Expressway near Winnetka Road.
It happened twice, once earlier in the evening and then again when the second round of storms came through.
The flash flooding stranded drivers forcing them onto the roofs of their cars as they waited for rescue crews with boats.
In addition to flooding roads, storms also downed trees, flooded basements and caused power outages.
ComEd says more than 50,000 customers lost power during the storm. As of 6:00 a.m. Sunday morning about 5,000 were still waiting for service to be restored.