Is Canada experiencing more tornadoes?
Watch above: After two tornadoes touched down in southern Ontario in just one week, Mark Carcasole looks at whether the twisters are becoming more frequent.
TORONTO – If a tornado touches down and there’s no one around to see or hear it, was it really there?
The United States gets the most tornadoes, annually, of any country in the world – but Canada comes in second.
On average, the U.S. reports about 1,300 tornadoes a year. While Canada reports a mere 80 annually, the real number is expected to be much higher: So much of the country is uninhabited that meteorologists suspect many tornadoes go unreported.
READ MORE: A look at tornadoes in Canada
Our country even has two tornado alleys: One, in Ontario, stretches from Windsor northeast toward eastern Ontario. Another is spread out across Alberta, Saskatchewan and Manitoba.
Most tornadoes in Canada occur in southern Ontario and the Prairies. Environment Canada
Most tornadoes in Canada occur in southern Ontario and the Prairies.
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On average about 17 tornadoes occur annually across Ontario and Quebec. In the Prairies, that number jumps up to about 43 a year.
READ MORE: State of emergency lifted but tornado cleanup continues in Angus
But are we actually seeing an increase in tornado activity across Canada?
The answer is complicated: Better technology makes them easier to detect and predict.
“What we do say is that we’re better able now to detect them, to be aware of where they occur. … And we’re better able to forecast them,” Peter Kimbell, warning preparedness meteorologist with Environment Canada, told Global News. “So all those things put together makes our database gathering and forecasting a lot better now. But it doesn’t really speak to how many occurred in the past.”
Kimbell also believes that with the popularity of tornadoes on the rise, there are more people chasing them, which increases the likelihood of tornado reporting, something the agency calls “ground-truthing.”
“If we use a spotter report of a tornado today, well, guess what? I don’t think there were many people chasing tornadoes, 20 years ago, 30 years ago, 50 years ago.”
Environment Canada senior climatologist David Phillips said Ontario is in the same “climatic regime” as America’s tornado alley: warm, moist air mixed with colder, drier air. When these come together, along with other factors such as wind shear, they can make the atmosphere quite unstable, leading to severe thunderstorms, which can spawn tornadoes.
“Tornadoes or severe thunderstorms don’t stop at the border,” Phillips added. “They come right in.”
This map tracks 56 years of tornado paths throughout the United States. Many of those tornadoes or severe storms make their way across the boarder into Canada. John Nelson/IDV Solutions
This map tracks 56 years of tornado paths throughout the United States. Many of those tornadoes or severe storms make their way across the boarder into Canada.
John Nelson/IDV Solutions
Kimbell said the Prairies also experience a similar climatic situation.
“[The Prairies] have the warm moist air coming up in the summertime and they have the cold fronts, and they also have the dry air flowing off the mountains,” Kimbell said.
Canada’s deadliest tornadoes
Tornadoes are rated on the Enhanced Fujita Scale which ranges from an EF0 (the weakest, with winds between 64km to 116 km/h) to EF5 (the strongest with winds between 419 to 512 km/h).
Only one F5 (this is before the scale was modified to the Enhanced Fujita scale) tornado has been reported – in Canada, in Elie, Man., on June 22, 2007. There were no deaths or injuries.
The deadliest tornado in Ontario occurred in Windsor, Ont., on June 17, 1946. That F4 tornado killed 17 people. But three of the four deadliest tornadoes in Canada occurred in the Prairies: On June 30, 1912, in Regina (28 fatalities); Edmonton, AB, on July 31, 1987 (27 fatalities) and in Pine Lake, AB, on July 14, 2000 (12 fatalities).
By comparison, the deadliest tornado in U.S. history occurred in the tri-state area (Missouri, Illinois and Indiana), killing 695 on March 18, 1925.
Editor’s note: This story has been corrected to note that the deadliest tornado in Ontario occurred in Windsor. A previous version of the story left out the province specification.
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