CatIQ raises Hurricane Debby remnants insured loss estimate to C$2.82bn

By Chris Munro

Feb 13 - (The Insurer) - CatIQ has slightly raised its insured loss estimate for the flooding that arose in Ontario and Quebec between 9 and 10 August last year as the remnants of Hurricane Debby passed through the region to C$2.817bn ($1.98bn).

The update is the fourth estimate that CatIQ has issued for the event, and comes six months after the flooding struck.

CatIQ’s latest estimate follows on the C$2.767bn that the Perils-owned risk modeller issued 90 days after the flooding occurred.

The company will issue a fifth and final update on the event on 8 August 2025, exactly 12 months after the storm struck Ontario and Quebec.

CatIQ’s loss numbers incorporate claims from both commercial and residential property, along with vehicle/motor.

The tropical depression that became Hurricane Debby first formed on 1 August 2024. The storm passed over the western Caribbean and southeastern US before being caught up in a large atmospheric trough on 7 August.

As CatIQ detailed, that trough then steered what had evolved into a post-tropical cyclone toward the Great Lakes, and the remnant low brought significant rainfall to eastern Ontario and southern Quebec.

According to the risk modeller, rainfall totals between 8 and 10 August topped 100 mm across a large area extending from eastern Lake Ontario, through Montreal and along the St Lawrence River toward Quebec City.

That caused widespread flooding along with extensive flood damage. The hardest-hit regions in southern Quebec suffered more than 200 mm of rainfall from the event.

“Since 2010, the insured losses from other remnant tropical storms in Ontario and Quebec have totaled more than C$500mn,” said Caroline Floyd, director at CatIQ.

“Prior to Debby, the largest tropical storm-related event for Quebec stemmed from the remnants of Storm Irene (2011), which at the time caused some C$101mn in insured losses.

“For comparison, the rainfall from Irene reached only 68 mm in Montreal, versus Debby’s 154 mm,” Floyd noted.

As Floyd explained, the Hurricane Debby remnants were especially impactful for residents of Quebec with more than 75,000 claims for personal property damage filed in the province.

“The average personal property claim size was not all that different from the flooding event in southern Ontario in July 2024, but the number of claims filed vastly differs, with Storm Debby generating nearly four times the number of claims as the Toronto flash flooding,” Floyd said.

The Hurricane Debby remnants was one of four major catastrophe events that struck Canada last year.

As this publication has previously reported, last year was the worst ever in Canada for insured catastrophe losses, with the industry taking a more than C$8.5bn hit.

Four events drove the majority of those losses: the Calgary hailstorm, which ranks as the second most costly catastrophe event for insured losses in Canada’s history; the remnants of Hurricane Debby, the third most costly; the Jasper wildfire, ninth; and the flooding in southern Ontario, 10th.