Environment Canada confirms EF2 tornado was part of deadly Ontario storm

Environment Canada has confirmed that an EF2 tornado touched down in Uxbridge on Saturday as a powerful weather system made its way through Ontario, tearing apart homes and knocking out power to thousands of people.

In a tweet, Western University's Northern Tornadoes Project said the May 21 tornado in Uxbridge was the first wind event in Canada to cause EF2 damage in 2022.

In an update posted Tuesday evening, Environment Canada said the group’s data has officially confirmed that an EF2 tornado was embedded within the leading edge of a derecho, which is a widespread and long-lived windstorm associated with a line of thunderstorms.

Environment Canada said the derecho developed near Sarnia late Saturday morning and tracked northeastward over Southern Ontario, crossing Ottawa Saturday afternoon.

“Damaging wind gusts were reported over a large swath of Southern Ontario as the severe thunderstorms raced through,” Environment Canada said. “After a preliminary analysis of the extensive damage in Uxbridge, Ontario, Western University's Northern Tornadoes Project Team has officially confirmed an EF2 tornado was embedded within the leading edge of the derecho.”

The agency said the tornado occurred near 1:15 p.m. on Saturday afternoon in Uxbridge and was found to have a maximum wind speed of 195 kilometres per hour.

Speaking with CP24, Environment Canada Warning Preparedness Meteorologist Gerald Cheng said the agency detected winds of just 46 kilometres per hour in Sarnia when the storms first tracked into Ontario from Michigan, but they eventually realized a mobile alert was needed as the storm picked up.

“We still issued a severe thunderstorm warning, but what really prompted us to make sure that those severe thunderstorm warnings were part of Alert Ready (warning system) was when we saw the wind gusts at the Kitchener Waterloo Airport; 132 kilometers per hour. At that wind speed up to 20 per cent of your shingles could be gone.”

Cheng said the wind speeds increased very quickly, leaving a small window to notify people.

“When we look at the wind speeds at 12:52 that day Saturday, Pearson reported gusts of 72 kilometres per hour — it’s a windy day. By 1 p.m., 120 kilometers per hour. So that escalated really quickly.

“We issued a warning for the City of Toronto at 12:45. But you can see the lead time wasn't much for people to take cover.”

The violent weather system left 10 people dead, caused extensive damage to trees and buildings and knocked out power to more than 1 million hydro customers in Ontario.

In a news release Tuesday, the City of Toronto said its cleanup efforts related to the storm remain ongoing. It said crews worked through the weekend to respond to storm service requests and that more than 2,900 requests have been received since Saturday.

“As of today, all available resources remain assigned to clean-up work, and there are a total of 45 crews out with cranes, bucket trucks and ground equipment,” they city said. “Crews prioritize responding to hazards to public safety or property. They are clearing roads as well as assisting Toronto Hydro by clearing trees from hydro lines.”

The city said it could still take several weeks to complete non-emergency cleanup work.

A number of municipalities have declared states of emergency, including Whitby, Ajax, Pickering, and Uxbridge.

Cheng noted that severe thunderstorm alerts were only added to the provincial “Alert Ready” system last June and said that while the alerts are useful tools, people need to remain vigilant about the changing weather conditions around them.

“Alerts don't get everybody. Your phone may be off. You may not be watching TV or listening to the radio interrupting broadcasts,” he said. “So it's so important that you know Mother Nature gives us clues, that when the conditions are deteriorating, don't wait for the alert. Take cover and seek shelter immediately, and stay away from tall objects like trees and power poles because they can fall on us.”

He said more outreach is necessary to make sure people remain alert about dangerous weather.