A heavy downpour hit Toronto in what seemed like an instant, causing unprecedented flash flooding on major highways, subways and commuter rails and plunging parts of the GTA into darkness. The storm, that began around 4 p.m., brought lightning and thunder and left trains stopped in their tracks, as subway lines were shut down intermittently due to power outages that left thousands of passengers waiting for alternate shuttles. Hundreds of thousands of customers across the GTA lost their power. The rising water levels turned roads into rivers, forcing people to abandon their vehicles and shutting down a part of the Don Valley Parkway. One vehicle took a dive into the floodwater after it drove into a sinkhole. Emergency crews scrambled to respond to a flood of 911 calls and city officials urged people to stay off the roads. At the height of the storm, Toronto Hydro reported that close to 300,000 residents were left without power across the Greater Toronto Area. The rains set a record for the city, dumping more than 125 millimetres in one day, leaving some to compare it to the flooding following Hurricane Hazel on Oct. 15, 1954, which saw 121 millimetres of rain dumped in one day. The storm also set a record as Ontario’s most expensive natural disaster. According to the Insurance Bureau of Canada, property damage caused by the storm was estimated at more than $850 million. With files from CTV's John Vennavally-Rao
