(CBS) -- Nearly 10,000 customers remain without power Thursday night after two waves of thunderstorms that slammed the Chicago area Monday and spawned eight local tornadoes.
Weather officials have confirmed the storms were derechos, or fast-moving, long-lived windstorms that can produce destruction similar to a tornado, but along a straight path, the National Weather Service said.
Monday's storms hammered the Midwest from Iowa to Ohio with straight-line winds from 80 to 100 miles per hour.
About 3,100 customers remain without power Thursday night, ComEd said. Power has been restored to 98 percent of affected customers, the company said.
The company expects to restore power to most customers by Thursday night, ComEd said. As many as 420,000 ComEd customers had been without power after the storms.
In northwest Indiana, at least 5,500 customers remain without power, down from a peak of 128,000 reported outages, according to NIPSCO. Damage included more than 500 downed power lines, the utility said.
Forecasters said Wednesday they have now confirmed eight EF-1 tornadoes spun off from the storms in northern Illinois and northwest Indiana. The twisters damaged property, but did not cause any injuries.
One passed within 3 miles of the National Weather Service office in Romeoville, where meteorologists twice notified a sister station in Central Illinois that they might have to hand over their weather-tracking duties and move to a tornado shelter.
"Thankfully that wasn't the case," meteorologist Matt Friedlein said. "But it certainly is one of our closest calls since we've been here."
That tornado packed winds up to 95 mph as it touched down 40 miles southeast of downtown Chicago in the northeast part of Plainfield. It lasted for about three minutes, beginning at 9:55 p.m., and traveled into portions of west and southwest Romeoville.
No one was injured, but it uprooted more than 50 trees and crossed Interstate 55, forecasters said. Some houses nearby sustained minor damage, mostly peeled siding and blown-out windows.
A second tornado with winds up to 110 mph touched down about 80 miles southwest of downtown Chicago in Earlville in LaSalle County. It lasted for two minutes, beginning at 9:16 p.m., and traveled 1.5 miles, clipping the west and southwest parts of Earlville. No injuries were reported, but the tornadoes downed numerous trees, damaged roofs and destroyed a garage.
Two more tornadoes touched down about 10:30 p.m. in the village of Grant Park in northwest Kankakee County, each with winds reaching 100 mph.
A fifth tornado that packed 100 mph winds touched down in southwest Kendall County about 5 miles west of Lisbon in area mostly covered in farmland. All of Monday's tornadoes were EF-1. The twisters damaged property, but no injuries were reported.
Three more tornadoes were confirmed Wednesday, one also near Grant Park and two more near Lowell and DeMotte in Indiana. Each twister packed winds of 100 to 110 mph, and lasted just a few minutes.
Damage from high winds was reported across the southwest metro area, which saw winds of 80 to 95 mph, Friedlein said.
"These tornadoes were not that much stronger than the conditions across the region," he said.
According to the weather service, wind gusts of 85 mph recorded in southwest suburban Tinley Park were the strongest in Cook County.
Just after 2 p.m. Tuesday, a 21-year-old man was electrocuted by downed power lines in the 8600 block of South Meade Avenue, Burbank Police said.
Nedal Doleh, who was visiting family, was found unresponsive in the back yard when emergency crews arrived, police and the Cook County Medical Examiner's office said. He was taken to Advocate Christ Medical Center in Oak Lawn, where he was pronounced dead at 3:40 p.m. according to the medical examiner's office.
An autopsy performed Wednesday found he died of electrocution and his death was ruled an accident, the medical examiner's office said.
At the time, ComEd employees were working nearby to repair power lines, police said.
Trained spotters measured 3.85 inches of rain in north suburban Highland Park between 6 p.m. and midnight, according to the National Weather Service. About 1.5 inches fell in southwest suburban Oak Lawn, with about two-thirds of an inch falling in a span of 20 minutes, forecasters said.
Rain water was being released into Lake Michigan to relieve storm sewer systems, according to a statement from the Metropolitan Water Reclamation District of Chicago. The gates on the Chicago River Controlling Works downtown and the gates at Wilmette were opened for several hours overnight.
As a result, swimming was banned Tuesday at all Chicago Park District beaches on Lake Michigan because of the water quality, officials said. All but one beach — Oak Street Beach — reopened to swimmers again Wednesday.
(Source: Sun-Times Media Wire © Chicago Sun-Times 2014. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)
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