Some Manitobans are wondering whether global warming is behind the recent wild weather in the province, which has been battered by a series of tornadoes and severe thunderstorms.

Four homes were destroyed when a tornado tore through Elie on June 22, one of seven that touched down in Manitoba that weekend.
(Wayne Hanna/Canadian Press)

Seven tornadoes tore through southern Manitoba last weekend, demolishing several homes and damaging many others and capping a spring that has brought much more rain than usual to many southern areas of the province.

The number of tornadoes is not uncommon; the province usually sees an average of nine twisters per year.

But their intensity — such as the one that demolished homes in Elie on Friday night, rated at F-4 on the Fujita scale  — is rare.

"It's very unusual to see an F-4 tornado in Manitoba, and indeed in Canada," said Danny Blair, a climatologist at the University of Winnipeg.

Blair said Manitoba should start preparing for the weather seen in the United States' so-called Tornado Alley — the area in the central U.S. where tornadoes are common — because he believes it's headed north to Manitoba and Saskatchewan.

"Down in Oklahoma and down in Nebraska and so forth, they really know how to respond to severe weather," he said.  "They don't play around with it. They take cover.

"In this part of the world, people don't really take it as seriously, unfortunately, as they should."

Farmers notice 'more extreme weather'

Some Manitobans wonder whether global warming or climate change is behind the odd weather.

"Farmers are seeing a lot of change in the weather. We've seen more extreme weather events," said Doug Chorney, a farmer and executive member of the Keystone Agricultural Producers.

"It's been a real challenge to grow and harvest any kind of crop in Manitoba in the last few years."

"It seems to be more and more devastating, the weather, as the years go on," said Rod Ewen, owner of a recreational vehicle park at Pelican Lake that was ripped to shreds in the weekend storms.

"It's something. I'm not sure what's causing it all, but I'll leave that to the meteorologists."

Blair said it's impossible to link one weather event to climate change — but said if more tornadoes come, that perspective might change.

"In the future, we may look back at this event and say that this was the beginning of a change in the frequency or intensity of storms," he said. "But as a singular event, it doesn't really have any ties to global warming."

Severe tornado would devastate Winnipeg

Even so, many scientists agree that more extreme weather is likely in the future, and some are starting to examine what that might mean for Manitoba.

John Hanesiak, an assistant professor at the University of Manitoba's Centre for Earth Observation Science, did a six-month study trying to predict what would happen if an F-4 tornado tore through southwest Winnipeg on a weekday afternoon in July.

This researcher's map of Winnipeg illustrates the path of a twister in red and an area of hail damage in blue in one possible scenario of a severe tornado.
(Courtesy of John Hanesiak/University of Manitoba)

"There's a fair number of residential properties and also commercial properties that would be either damaged or completely destroyed in that event," Hanesiak said.

"Typically in this sort of scenario … we'd have about 100 people killed and about 3,000 would be sort of injured and up to actually $3 billion in damage."

The estimates were based in part on other urban tornado strikes in Canada and the United States. Similar storms killed dozens of people in Edmonton in 1987 and Oklahoma City in 1999.

On average, a tornado touches down in Winnipeg every 10 to 12 years.

"We didn't do this project to be alarmists," Hanesiak noted. "We did it to bring the issue to the table."