Calgary hailstorm inflicts $2.8 billion damage, thousands of claims

On August 5 2024 a powerful supercell thunderstorm swept northern Calgary, producing hailstones as large as hen eggs and strong winds that shattered windows, dented vehicles and damaged roofs. The event affected roughly 35,000 buildings, generated more than 130,000 insurance claims and was estimated to cause about $2.8 billion in insured losses, making it Canada’s second‑costliest insured disaster. Calgary International Airport suffered roof damage and gate closures, and WestJet withdrew 17 aircraft for repairs.

The storm highlighted the vulnerability of condo plumbing systems in the city. Heavy rain can overload shared drainage, cause backups in underground parking and mechanical rooms, and strain sump pumps, prompting property managers to adopt emergency plumbing plans to limit damage and downtime during intense summer storms.