The Insurance Bureau of Canada (IBC) says its initial estimates show severe storms and flash flooding which hit parts of Ontario over the summer caused more than $340-million in insured losses. The figures are based on information from Catastrophe Indices and Quantification Inc. (CatIQ).

More than $80-million, close to 25 per cent of the insured losses, went toward replacing or repairing storm-damaged vehicles.

Ottawa was the hardest hit by the summer storms, reporting intense flash flooding, downpours and violent wind. All told, five storms in the summer of 2023 were designated catastrophes, defined as severe weather events with insured damage estimates that total more than $30-million.

The first, occurring on July 20 and 21 when a cold front crossed southern Ontario and Quebec, led to thunderstorms, two confirmed tornados, large hailstones and downpours which caused flooding.

A period of hot and humid weather next culminated in severe thunderstorms across southern Ontario July 28 and 29. “Multiple supercell thunderstorms developed,” the IBC reports.

August 3 storms caused the second highest amount of damage – more than $100-million in insured damage – as storms knocked down homes under construction, downed trees and powerlines and damaged vehicles. “Flash flooding left many vehicles partially submerged.” 

A cold front August 10 caused thunderstorms across Ottawa to cause more than $70-million in damages. And finally, the remnants of Hurricane Hilary caused the most damage between August 23 and 25 in southwestern Ontario. “This led to a series of heavy storms, producing significant rainfall, multiple tornados and large hailstones. More than 200 millimeters of rain fell on some communities, resulting in flooded roads, basements and properties.” The hurricane-fuelled storm reportedly caused more than $100-million in insured damages.