Tornadoes touch down across the country, often without specific warnings to residents in the storm’s path, experts say.
Dave Sills, executive director of Western University’s Northern Tornadoes Project (NTP), says they found Environment Canada “didn’t do very well” in alerting people to tornadoes that touched down across the country between 2019 and 2021.
“About 70% of tornadoes had no tornado warning – and that included most of the EF-2 tornadoes we have in our database,” he said, referring to tornadoes that can cause “considerable damage”, in particular by tearing the roofs of the houses. .
Tornadoes are less common in Canada than in the United States, where they are regularly seen in “Tornado Alley” – the region that stretches from northern Texas to South Dakota. US data indicates that tornadoes regularly move eastward, closer to more densely populated regions, the researchers said.
In Canada, tornadoes most often occur in extreme southern Saskatchewan, Manitoba, and Ontario, but can also occur in southern Alberta, southern Quebec, and New Brunswick. NTP data suggests peak tornado season in southern Ontario is now more likely later in the summer.
Although data from the project does not indicate that there are more tornadoes in Canada – or that climate change is affecting their frequency – population growth and the expansion of suburban areas mean that they are increasingly on the way to the houses.
“Everyone sees what’s happening in the United States and is like, ‘Well, that’s not happening here. “But during our peak months between June and August, anything in the United States is possible here,” Sills said.
Environment and Climate Change Canada, the federal department responsible for the country’s weather service, says that while warnings are not issued for every tornado, they would have been issued for many of the thunder and wind events that spawned them.
“We can mention in a severe thunderstorm warning that there is a risk of a tornado,” said Ken Macdonald, executive director of national programs at ECCC.
“Weather radar is a great tool for the forecaster, but it doesn’t actually see tornadoes. It sees the thunderstorm and can see that there may be a rotation that could produce a tornado, but it doesn’t actually tell you there’s a tornado.”
“Like the ground is curling up towards me”
Tornadoes can strike suddenly and with few warning signs, which James Blacksmith knows first hand. He received no alerts when a tornado formed as he crossed Manitoba Highway 83.
The sky showed no indication of an impending storm, Blacksmith told CBC Radio. It wasn’t until the wind suddenly picked up that he knew there were problems.
“Something hit the roof of my Jeep. So I thought it was going to start hailing, so I pulled over in a farmyard,” he said. “I pulled up under tall pine trees…and there was a white truck that pulled up next to me.”
The next thing he knew, a tornado had formed, touching down near Scarth, Man. “It felt like the ground was rolling towards me, like a wave,” he said.
A tree fell on Blacksmith’s vehicle, pinning him to the spot. The nearby truck was pulled into the tornado vortex.
The truck was thrown through the air, killing its two teenage passengers. Blacksmith walked out with injuries that continue to plague him today.
“The tree that fell kind of saved my life, I guess. It held me back for a while,” Blacksmith said.
Environment Canada classified the tornado as EF-3, with winds of up to 260 km/h, after initially rating it as EF-2.
Canada’s vast geography makes forecasting tornadoes difficult. Large tracts of uninhabited land and many forested areas mean that many storms go unnoticed.
“Not every situation where a severe thunderstorm caused wind damage, for example, wouldn’t we go and investigate and figure out what it was? A tornado or was it wind damage?” McDonald said. “We haven’t been able to put the resources in to do that.”
Damage from an EF-0 tornado, the weakest possible tornado, can resemble a strong wind event, such as the derecho that swept through Ottawa last Mayhe added.
Improvements to the forecasting system in progress
This is where the Northern Tornadoes Project comes in. The project’s research team tracked the number of tornadoes across the country using historical data, high-resolution satellite imagery and eyewitness reports.
In addition to documenting as many tornadoes as possible, their work uncovered a previously unknown major tornado that hit Quebec in 2017.
“There will be more impacts just because of population growth and the expansion of our suburban areas,” said Greg Kopp, NTP researcher and ImpactWX Chair in Severe Storm Engineering at Western University. of London, Ontario.
“And so to separate all of that out, we really have to do that – those detailed studies – to try to find everything so that we have a good basis for comparison.”
What will I do when I receive this warning? Where will I go?– James Forgeron
Macdonald said Environment Canada is working with Sills and Kopp to better understand the impact of tornadoes on Canada. Ongoing upgrades to the country’s weather radar systems will also help forecasters better predict the risk of a tornado, he added.
But when it comes to alerting the public, Macdonald notes that the agency aims to strike a balance. Sending notifications for uncertain weather events that do not materialize could reduce trust in the system, he said.
“We looked at a single example of a situation last summer where a tornado formed [in Ontario]”, he said. “There could have been in the order of 25 major thunderstorms scattered all over the place. One of them produced a tornado.”
Blacksmith admits he’s not sure an alert would have done much good given he had few safe places to turn.
“What am I going to do when I get this warning? Where am I going to go? I don’t know what’s going on,” he said.
Request a building code update
With growing knowledge of the frequency and potential impact of storms, Sills and Kopp say it’s time to reconsider how homes are protected against the threat of tornadoes.
Hurricane straps – metal brackets that secure a house’s roof to its walls – are an option not yet required for most home construction in Canada.
“We discovered that the weakest link in the structure is actually the roof attached to the walls,” Kopp said.
According to Kopp, there is resistance to mandating hurricane straps due to the added cost. There are also questions about the effectiveness of the design for tornadoes. But he adds that there is evidence that hurricane straps can protect a home’s inhabitants and the wider community.
“This little piece of metal is strong enough to hold the roof against the walls and in a tornado up to EF-2.”
In a statement, the Canadian Commission on Building and Fire Codes says hurricane straps are needed in seven areas — in parts of Alberta, Newfoundland and northern Canada — that are experiencing storm surges. “higher wind loads”.
He goes on to add that climate change adaptation is a “policy area of focus” for the 2025 and 2030 editions of the National Building Code, a model code. Building codes fall under provincial and territorial jurisdiction.
Kopp says he sees positive moves toward putting hurricane straps in place. For example, he says a major home builder in Barrie, Ontario. — a city hit by a devastating tornado in 2021 — is adding them to new homes.
“We have to do it because it’s the right thing to do,” Kopp said.
“Let’s just solve this problem with a simple solution, which is to put these things in place and we’ll be good to go.”