UPDATED 06/22/11 11:53 p.m.

CHICAGO (STMW/CBS) — Commonwealth Edison says nearly all of its customers who had power knocked out by Tuesday night’s storm, including 189,000 still without power late Wednesday afternoon, “could” have electricity restored by late Thursday.

ComEd has had about 400 crews out since the storm blew through the area working to restore power to hundreds of thousands of customers who were left in the dark. In total, about 433,000 customers lost power at some point because of the storm.

The storm, which hit Chicago about 9 p.m., prompted numerous tornado warnings throughout the area, according to the National Weather Service. By 9:30 p.m., the most severe portion of the storms had passed to the northeast. CBS 2’s Kristyn Hartman reports.

Downed trees and power lines have ComEd crews scrambling to restore power and Metra working to removed downed trees and branches from tracks.

As of 4 p.m. Wednesday, about 189,000 ComEd customers across the area were without power, according to ComEd.

In Chicago, about 1,700 customers were still without power, down from 65,000 at one point. The near western suburbs still had about 34,000 without power as of Wednesday afternoon.

The hard-hit northern suburbs still have about 137,000 customers powerless as of 4 p.m. In the south suburbs, about 18,000 customers were without power, while in the farther western suburbs, about 600 were without electricity.

“We estimate 90 percent [of those who at one time or another had lost power] will be restored with power by midnight tomorrow [Thursday night],” ComEd spokeswoman Alicia Zatkowski siad.

At Northwestern University’s Evanston campus, 42 buildings were without power, according to an alert on the school website. Some of those have backup generators and ComEd crews were working to restore power, but as of Wednesday morning, it was not known how long before electricity would be completely restored to the campus.

In Elmhurst, summer advising and registration for new students at Elmhurst College has been canceled because of a power outage, according to the school. Summer classes for Wednesday have also been canceled.

All court proceedings at the Cook County Courthouse in Maywood were canceled for Wednesday following a loss of power. All civil cases are rescheduled to June 29, at the same times and courtrooms as previously scheduled.

Traffic, misdemeanor and felony cases of defendants in custody of the county are rescheduled for Friday, also at the same time and courtroom. Cases for individuals out on bond are rescheduled for July 27.

The storm also knocked out power to post offices in the north, west and northwest suburbs. The Des Plaines, Glencoe, Golf, Lake Bluff, Lake Forest, Mount Prospect, Park Ridge, Prospect Heights, Rolling Meadows, and Wheeling post offices were without power, according to a release from the U.S. Postal Service.

Generators have been sent to the post offices to make sure letter carriers will be able to sort and deliver mail. “Where feasible,” the release said, “deliveries will be attempted and retail service will be available.” Postal officials are preparing to resume full delivery and retail service on Thursday.

Airlines at O’Hare International Airport have already canceled 250 flights Wednesday and are experiencing delays of up to 20 minutes, according to the city Department of Aviation. Midway Airport is operating normally.

In Northbrook, the severe weather brought wind gusts up to 68 mph and .25 inches of rain. About 5,700 ComEd customers in Northbrook were without power, the release from the village said. There are also downed power lines throughout the village.

More than 10,000 Mount Prospect residents were left without power in the wake of the storm, a release from the northwest suburb said. For those whose air conditioning has been knocked out, cooling centers are available at the Village Hall, 50 S. Emerson, and the Community Connections Center, 1711 Algonquin Rd.

In Des Plaines, more than 11,000 remained without power late Wednesday afternoon and in Evanston, 2,000 remained in the dark, according to releases from the suburbs.

Several sections of Skokie are without power and there is extensive damage to trees throughout the community, a release from the northern suburb said.
Naperville reports minimal damage from the storm. Of approximately 58,000 ComEd customers in the west suburb, a total of 826 lost power, a release said. All had had power restored by Wednesday morning.

Meteorologist Samuel Shea said numerous funnel clouds were reported in the suburbs, including Naperville, Grayslake and Sugar Grove, but there were no confirmed reports of tornadoes as of Wednesday morning.

Three teams of meteorologists from the National Weather Service will tour some of the hardest hit parts of the area Wednesday to determine whether damage was caused by tornadoes or straight-line winds, such as the 80 mph gusts reported in Wheeling.

The weather service has received numerous reports of wind-related damage. The intersection of North and Ridgeland in north suburban Waukegan was clogged with downed branches, some more than 30 feet long, according to the weather service.

Twelve-inch-wide tree branches were downed near north suburban Skokie’s village hall, while the side of an aluminum shed was blown off in southwest suburban Bolingbrook.

The storms even damaged a pollen-catching machine atop Gottlieb Memorial Hospital in Melrose Park that provides the Midwest’s official daily allergy count, according to the hospital. A doctor had to manually reshape the blades of the pollen-catching machine to put it back in working order, just in time to measure Wednesday’s high mold count.

“Winds that high can bring down tree lines, they can bring down power lines, they can tear roofs off buildings,” Meteorologist David Beachler said Tuesday. “It depends on how it’s coming together, it depends on the structural integrity of buildings … Nonetheless, the consistent theme with [the] storm is there are a lot of trees down and power lines down.”

Weather conditions and debris on the tracks at several locations kept five trains stranded on the Union Pacific/Northwest line into the early morning hours Wednesday, hours after they were supposed to arrive at their destinations, according to Metra’s website.

Four trains were also stopped on the Union Pacific/North line during the height of the storm. Strong winds also blew at least one tree onto the Milwaukee West Line, which runs between Chicago and Elgin, Metra spokesman Michael Gillis said.

Gillis could not immediately say how many people had been stuck on the trains that were stopped late Tuesday.

Some trains during the Wednesday morning commute were delayed up to 30 minutes because of lingering track obstructions and signal problems near Western Avenue, all related to the weather, the website said.

On the CTA, Yellow Line service was suspended Wednesday morning because of ComEd work, according to the CTA’s website. By noon though, service had been restored, but there were still “minor … residual delays.”

There is a 50 percent chance of showers, but no storms, Wednesday night, according to the weather service. Clouds and showers, with high temperatures in the mid-60s to lower 70s are the story Thursday and Friday, but according to the weather service, it should be mostly sunny Saturday, with highs in the lower 70s.

© Sun-Times Media Wire Chicago Sun-Times 2011. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed

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