A severe convective storm outbreak that swept across the US Midwest between August 9 and 11 could generate insured losses running into the billions of dollars, according to a recent report from Guy Carpenter.
The reinsurance broker, which is part of Marsh, said the event could rank among the 10 largest US severe convective storm (SCS) insured loss events on record, based on initial damage reports.
According to Guy Carpenter, the storms developed as a slow-moving cold front affected Wisconsin, Illinois, Iowa, Indiana, Ohio and surrounding states, with activity impacting several major metropolitan areas, including Chicago, Indianapolis and Columbus.
Guy Carpenter highlighted the severity of the wind threat, noting that the strongest reported gust reached 97 mph in Sugar Grove, Illinois, a suburb of Chicago.
Multiple states experienced damaging winds of 60-80+ mph, while hail reached 3.5 inches in diameter.
The outbreak also reportedly produced isolated tornadoes and intense rainfall, with rates of 2-3 inches per hour and multi-day rainfall totals potentially exceeding 9 inches.
“Given the severity of winds in the Chicago, Indianapolis, and Columbus, OH metropolitan areas, insured losses are likely to be measured in the billions of dollars,” Guy Carpenter said.
The firm added, “It is plausible given initial reports of damage that the last several days of severe weather activity could breach the top ten largest US severe convective storm insured losses list.”
The latest outbreak follows a substantial severe weather event in the Midwest in late July, which was also identified as having the potential to become a top-10 US severe convective storm insured loss event.
According to broker Aon, a top-10 ranking would imply an industry insured loss of approximately $5 billion or more.
