(MCT) — A line of powerful thunderstorms rolled through the Chicago area Wednesday evening, forcing a temporary halt to commuter train traffic and canceling hundreds of flights in and out of Midway and O'Hare International airports.
The storm system threatened to produce violent hailstorms and tornadoes, but few, if any, had materialized by Wednesday night. Still, more than 34,000 people were left without power, and passengers were stranded on Metra trains for an hour or longer.
The delays were a particular nuisance for Blackhawks fans eager to get home to catch the first game of the Stanley Cup Final.
"Stuck stopped on the train right now," Colin Ogden of Normal, Ill., wrote Wednesday evening on Twitter. "This is unreal!!! Doesn't metra know the Hawks play tonight!!!"
Metra spokesman Tom Miller said the delays were caused by unsafe conditions such as high winds and flash-flood and tornado warnings.
The National Weather Service had warned of dangerous and potentially destructive conditions, including wind gusts of up to 75 mph. The dire predictions spurred precautions all across the Chicago area.
The White Sox game against the Toronto Blue Jays was canceled. ComEd scheduled extra work crews in anticipation of damage and power outages.
The city of Evanston closed its facilities and sent workers home early for the first time since the blizzard of 2011, said city spokesman Eric Palmer. The city closed all facilities and beaches, and officials called around to construction sites to make sure materials and equipment were secured.
"We're taking this seriously," Palmer said. "We want to make sure that we can get our staff home safely."
Evening classes and final exams were canceled on both the Evanston and Chicago campuses of Northwestern University. The university's library and athletics center were also closed.
Officials in Glenview, which experienced major flooding during a storm in April, made sandbags and shovels available to residents.
As the series of isolated thunderstorms started rolling in, warnings of conditions ripe for tornadoes had residents on high alert. A tornado siren was activated in Aurora, but there were no indications Wednesday evening of a touchdown.
Some funnel clouds were reported west of Chicago, and the National Weather Service said a tornado might have touched down in the area of Shabbona and Sleepy Hollow roads in DeKalb County, where law enforcement sources reported tree and power line damage.
By Wednesday night, the storms had produced scattered problems.
Lightning was the suspected cause of a Lemont house fire when thunderstorms swept through the southwest suburbs, said Lemont Fire Chief Carl Churulo.
Chicago Fire Department spokesman Larry Langford said Wednesday night that there were surprisingly no instances of lightning-induced fires in the city. The department also had yet to be notified of any downed trees or other damage caused by the storm.
"We were prepared for more, we thought there would be more," Langford said.
By 9 p.m., the storm had left 34,462 customers across the area without power, said ComEd spokeswoman Ashley Dennison, including 142 customers in Chicago.
The biggest impact from the storm's early hours seemed to be the halting of Metra commuter trains.
Inbound and outbound trains on Metra's Burlington Northern Santa Fe, Union Pacific Northwest and Union Pacific West lines were grounded due to the severe weather, leading to delays of about 40 to 85 minutes.
A flood watch was in effect across the Chicago area from 4 p.m. through late Wednesday, with heavy rain predicted between 6 and 11 p.m. Rainfall was expected to total 2 to 3 inches in some places.
Showers and thunderstorms are predicted into early Thursday, then the day will turn mostly sunny and cooler, with high temperatures around 70.
Tribune reporters Michael Holtz, Alexandra Chachkevitch and Heywood G. Hoffman contributed.