Saturday's storm knocked out power to tens of thousands, and at the height of the storm, the lights were out for about 160,000 customers.
However, more than 14,900 customers were without power Sunday afternoon. About 3,200 are in the north region, 6,200 are in the south region and 4,500 are in the west region.
ComEd has restored electricity for 76,000 customers.
The power company says this has been a record-breaking summer. A peak usage record was shattered last Wednesday with customers using 23, 753 mega-watts. That broke an old record of 23, 618 on August 1, 2006.