As of that time, power was out for more than 40,000 ComEd customers in the southern suburbs, and NIPSCO says just under 5,000 customers were affected in northwest Indiana.
Some North Shore residents were also reportedly without power Friday night.
The storms also disrupted travel out of both of Chicago's airports by as much as an hour.
Besides strong winds, the storms also brought drenching rains that caused some flooding.
The severe storms left a trail of damage from the suburbs all the way into northwest Indiana.
In this summer of intense heat the storms are to be expected, and so is the aftermath around the Chicago region.
One homeowner found roof damage in Romeoville, and a playground in Bolingbrook suffered damage in the storm as well.
Wrecked umbrellas and soaked clothes were visible as people ran for cover in Plainfield at the area's Wal-Mart.
In Channahon, the wind hurled a gazebo into a hot tub, a graphic reminder of the nastier side of high temperatures.
"I get a lot of wind out here a lot, a little windstorm, and this was the biggest so far, and it did some damage," said homeowner Ryan Anderson.
The power of mother nature was on display in Joliet, as a pool that would normally have been full was emptied.
Dismal skies in Will County were mirrored in northwest Indiana, as the storm barreled in on Whiting.
Back in Illinois, viaducts in Bridgeport quickly became impassible after raging downpours.
Still, as summer storms go, this one was relatively mild compared to others so far in 2010, keeping the city's magnificent mile busy.
Earlier Friday: Cool relief at the water park
One way to cool off earlier in the day before storms hit: head to the pool.
"It's too hot for a fan, it's too hot for air conditioning - it's hot enough for the water," said one pool-goer at Splash Station Water Park in Joliet.
The water park was packed with those looking for some relief. Later in the evening, it cleared out as storms approached Will County.
With temperatures climbing into the middle 90s and a heat index that makes it feel like its 100-plus degrees, some parts of northwest Indiana and several counties around Chicagoland, including Will County, remain under a heat advisory.
"We try to make sure that everybody gets in the water at some time," said Don Dickerson of Splash Station Water Park. "Try to make sure that everybody has something to drink."
On the hottest day of the year so far, city workers conducted well-being checks on the elderly, while warning everyone about the danger of heat stroke and heat exhaustion caused by the extreme weather.
"Be sure to drink plenty of water - at least 8 glasses a day," said Dr. Bechara Choucair of the Chicago Department of Public Health. "Second, avoid going out in the heat during the hottest part of the day."
As Chicago opened cooling centers throughout the city, veterinarian Dr. Tara Clack of Burnham Park Animal Hospital says remember the family pet needs protection from the heat too.
"Remember that these guys are just like humans as far as getting overheated," said Clack. "It's very important to keep your animals hydrated."
As Chicago sizzles, some residents say they are doing what they can to enjoy the warmth.
"It's summer in Chicago," said Mark Boyle, saying he'll just "try to make the most of it."
