A devastating derecho that swept through Ontario and Quebec earlier this month could be one of the costliest insured loss events in Canada on record, according to Aon’s latest Weekly Cat Report.


The storm travelled over 621 miles across Canada’s most populous regions on 21 May, with the provinces of Ontario and Quebec hit hard, including the metro regions of Toronto, Ottawa, Montreal and Quebec City.

At least 10 people were killed by the storm, with dozens left injured. At least one million people across Southern Canada were left without electricity as the storms passed, Aon said.

Elsewhere, Ontario’s Hydro One reported large electrical transmission towers near the Canadian capital Ottawa were toppled, with over 1,000 power poles knocked down across the province.

Aon said the storm is expected to be “a substantial event” for the country’s insurance industry.

“The insured loss was very likely to end as one of the top five or top 10 costliest industry events for the severe convective storm peril on record. It may also end as one of the more expensive Canadian insured loss events on record regardless of peril,” Aon said.

The largest ever insured natural catastrophe event in Canada’s history was the Fort McMurray, Calgary wildfires in 2016 which generated C$3.6bn ($2.8bn) of losses. Floods that engulfed parts of southern Alberta in 2013 were the second costliest event having left insurers with C$1.7bn of losses.

And ice storms that hit Ontario and Quebec in 1998 and which caused C$1.3bn of losses are the third largest insured event.

According to figures from AM Best, in 2020 Intact Group was the largest property and casualty writer in Canada with C$10.3bn of direct premiums written and a market share of 14.3 percent.

Desjardin Group and Aviva Canada were in second and third place respectively with DPWs of C$5.7bn and $5.6bn, along with market shares of 8 percent and 7.8 percent.

Lloyd’s Underwriters (C$4bn and market share of 5.6 percent) and Wawanesa Mutual Insurance Company (C$4bn and 5.5 percent) made up the top five.

US severe convective storm losses set to surpass $10bn

The final weeks of May have also seen the US impacted by convective storms. Beginning 19 May, Aon reported that a series of areas of low pressure impacted much of the eastern two-thirds of the US which left two people dead and dozens more injured.

According to Aon, aggregated US economic and insured losses were each estimated into the hundreds of millions of dollars.

“The overall economic loss – which includes uninsured or underinsured damage costs – will be even higher,” Aon stated.

“This continues an active stretch for the peril in the US which has been consistently busy on a near weekly basis since early March.

“The country is once again on pace to well surpass the $10bn insured threshold for the peril, which it has done in every year since 2008,” Aon added.