— killing at least one person, downing power lines and trees and ripping off roofs in several communities.

The death occurred in the town of Durham, police confirmed without giving details. A tornado reportedly touched down in the community, about 50 kilometres south of Owen Sound near Lake Huron and 180 km northwest of Toronto.

Environment Canada meteorologist Geoff Coulson said at least three buildings in Durham suffered damage when the storm hit around 4 p.m. ET. Without confirming a tornado, the agency warned of potential twisters occurring through Thursday evening.

In the wake of eastbound storms that swept through the Greater Toronto Area, the City of Vaughan declared a state of emergency. The city just north of Toronto opened shelters for residents displaced from their homes.

About 120 seriously damaged homes in Vaughan had to be evacuated, said York Region Fire Chief Greg Senay.

The powerful storms overturned vehicles, lifted roofs off homes and pulled air conditioners out of windows.

The storm gradually lost some power as it crossed the eastern part of Ontario. Late Thursday night, the last tornado watches for the Kingston area were dropped by Environment Canada.

Severe thunderstorm warnings remained up for an area stretching from Pembroke to Ottawa and Brockville.

An estimated 69,000 Hydro One customers were reported to be without power in the wake of the storms, while Toronto Hydro said an unknown number of its customers were without power due to multiple outages.
Flights affected

The severe weather caused dozens of delays and cancellations at Toronto's Pearson International Airport.

"It's the same as any time we have a storm. It takes some time to come back to normal," Greater Toronto Airports Authority spokeswoman Trish Krale told CBC News, without elaborating on how many flights were affected.

Pearson has a policy requiring ground crews to be pulled from outside work when lightning strikes are recorded in the vicinity of the airport, she noted. "There was quite some time the ground crews were inside," Krale said.
Barn thrown

"It was a full-blown tornado, without any doubt," Durham-area resident Philly Markowitz said.

A barn on her property was picked up and thrown into her home, she told CBC News.

"The house directly across the road from me is missing a roof," she said. "The house next door to me — the barn is missing. We can't find the barn."

[link to www.cbc.ca]