EMBED >More News Videos Sunday's storm caused a tree to fall over a vehicle, trapping the driver inside, in the Bucktown neighborhood.

EMBED >More News Videos The water flooding the Edens expressway last night has receded, but, at one point, the water rose up to three feet high.

MY FEELINGS ARE HURT! New Edition canceled b/c of the rain inside UIC Pavilion. WHAT?! pic.twitter.com/u98VdbTCT2 — kathychaney (@kathychaney) July 24, 2016

EMBED >More News Videos Being cautious during the summer months can help prevent heat related illness.

CHICAGO (WLS) -- Investigators were on site Monday to determine what caused the collapse of a canopy at the CTA Blue Line stop at the Illinois Medical District. Normal Blue Line service was restored in time for the Monday morning commute.An aluminum canopy covering a pedestrian walkway was knocked onto the CTA Blue Line tracks at the Illinois Medical District station at about 7:00 p.m. A CTA spokesperson said it was immediately unclear if lightning or wind, or a combination, were to blame. The concrete ramp was still intact. No injuries were reported.Landscaping crews along the Eisenhower have been finding debris along the expressway, such as sheet metal and plexiglass that matches the pattern of the canopy that fell away.The Paulina entrance for the Blue Line is closed and nearby large tree branches are down.When severe storms came through the area last night, flashes appeared along this stretch of the Blue Line east of Ogden and part of the pedestrian canopy blew over."It's very scary. I want to know where it came from and how it happened because I ride the Blue Line every day," said Sheila Hill, a Blue Line passenger."I've never seen anything like it. It was amazing to me. It was just a boom and sparks and debris flying all over the tracks. I don't know how that's going to be fixed anytime soon," said another passenger, Victor Stroud.Crews worked through the night to restore service after the storm for the Monday morning commute.Two sisters driving along the Eisenhower took cell phone video of the dramatic flashes near the Illinois Medical District stop.Blue Line service was restored for the Monday morning commute, but some passengers did have a detour around Paulina."The only difference I noticed is that the exit I usually take was just blocked off and boarded up. So I kind of had to go around and take the Ogden exit," said passenger Adriel Cansino.The CTA says the incident is still under investigation.CTA Red and Brown lines were also temporarily stopped due to tree debris falling on the track at Armitage due to the Sunday storms. Brown Line service was impacted between Loop and Southport. Red Line service was impacted between Belmont and Grand.Meanwhile, the storms left people stranded at O'Hare, where 291 flights were cancelled Sunday. More than 80 were cancelled as of Monday morning.The Chicago River was near flooding level Sunday night in the Albany Park neighborhood where residents within a block of the river were told to remove their vehicles to avoid flood damage. Ald. Margaret Laurino (39th Ward) said city workers were working on mitigating the issue, according to her Facebook page.In Bucktown, the storm brought down utility poles and trees, including one over a vehicle on Seeley Avenue. The driver needed help getting out of the car."When (the tree) snapped it started pinning one guy in his car, so he couldn't even get out of his car," said witness Ronald Ayala.Most of Sunday was quiet and dry. By the end of the night, most counties in northeast Illinois and Lake County in Indiana saw severe thunderstorm warnings. Starting at about 5 p.m., Cook and Lake counties, including the communities of Rolling Meadows, Elk Grove, Niles and Evanston, saw storms and large hail. A second storm system dumped heavy rain throughout Chicago between 6 p.m. and 7 p.m.The heat continued Sunday, which was the fourth day in a row with temperatures in the 90s. A heat advisory was in effect for most of the Chicago area most of the day with Heat Index values reaching upwards of 112 degrees Sunday afternoon.Some of the 326 boats which participated in the 108th Chicago Yacht Club Race to Mackinac encountered storms late Saturday and early Sunday.The 333-mile race from Chicago to Mackinac Island in northern Michigan kicked off on Saturday. Arete reached the island first, according to the race's Facebook page The event is the longest freshwater sailing race in the world.A hot and humid Saturday was punctuated with evening thunderstorms that swept through the Chicago area, causing high winds, heavy rains, flooding and the delay of a Coldplay concert at Soldier Field.The storms caused power outages, too. As of Sunday afternoon, 99 percent of the nearly 60,000 ComEd customers who lost power had service restored.The Edens Expressway flooded Saturday night but has since receded. At one point, the water rose up to three feet high.The water was so high at the Winnetka underpass on the Edens, a spot that tends to flood often, several people got stuck. Five cars with people inside became stuck on the Edens in the deep water and had to be rescued.When help arrived, emergency crews brought a raft out to rescue the stranded motorists.No one was hurt but we're told several homes in the area also flooded.The north suburbs, particularly around Winnetka and Northfield, saw the most rain with upwards of four inches.Many communities saw major flooding, but the heavy rain also canceled the New Edition concert at the UIC-Pavilion due to flooding inside the venue.