Storm hits GTA as rain, strong winds and tornado risk loom over southern Ontario

A severe storm cut across the Greater Toronto Area on Wednesday afternoon, downing power lines and flooding some streets as Environment Canada warned of heavy rain, large hail and the risk of a tornado in much of southern Ontario.

The weather office issued multiple emergency alerts for extreme weather in parts of the GTA as skies darkened to almost nighttime levels over the city’s downtown and hail pummelled neighbourhoods further north. 

Subway service was also suspended on a stretch of one of Toronto’s main lines during the afternoon rush hour due to flooding.

Toronto police said they have received reports of fallen trees and downed power lines in several locations across the city. 

“Please use caution when driving,” police said in a post on X. “Slow down and drive according to the road conditions.”

The storm also caused numerous flight delays at Toronto’s Pearson airport on Wednesday evening.

“Passengers are encouraged to check their flight status directly with their airline before travelling to the airport,” it said in a post on X.

Videos from across the region shared on social media showed large hail pummelling cars in parking lots, and vehicles stuck in flooded stretches of Toronto roads. 

A severe weather alert stretched from near Sarnia east to Peterborough and north to Barrie, with areas such as Windsor and parts of cottage country under a yellow watch earlier in the day.

Environment Canada said hard-hit areas could see torrential downpours, ping pong-sized hail and wind gusts up to 110 kilometres an hour.

The primary concern was the possibility for damaging winds and torrential rains. 

The storm came after parts of Ontario were lit up with lightning strikes and inundated by heavy rains by passing storms Wednesday morning. 

This report by The Canadian Press was first published Sept. 2, 2026.