Midwest storms could be costliest in years
The severe thunderstorm outbreak that swept across the U.S. Midwest earlier this month may become one of the costliest in insurance history, with losses potentially exceeding $5.1 billion, according to reinsurance broker Guy Carpenter.
Winds over 90 mph left a trail of damage
From August 9 to 11, multiple rounds of severe convective storms hit Wisconsin, Illinois, Iowa, Indiana, Ohio, and neighboring states. A slow-moving cold front fueled the storms, producing wind gusts above 90 mph in parts of the Chicago area. The highest recorded gust reached 97 mph in Sugar Grove, Illinois.
The broker’s early August report described widespread damage: wind gusts of 60–80 mph, hail up to 3.5 inches in diameter, isolated tornadoes, and rainfall rates of 2–3 inches per hour. Some areas received multi-day totals surpassing 9 inches. Ohio also faced straight-line wind events, with Columbus recording an 82 mph gust.
Illinois has confirmed three tornadoes from the outbreak. Field surveys may reveal more. The state has already recorded over 200 tornadoes in 2026, making it only the second state—after Texas—to reach that number in a single year. Texas set its record in 2015 with 245 tornadoes.
Insured losses could rank among the top 10
Guy Carpenter warned that the storms’ financial impact could be substantial. The broker stated that given the severity of winds in Chicago, Indianapolis, and Columbus, insured losses would likely reach billions of dollars. The event might enter the top ten costliest U.S. severe convective storm losses since 1995.
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The current 10th-ranked event, from May 2014, caused damage totaling $5.1 billion. For this month’s outbreak to surpass it, final losses would need to match or exceed that amount. Such an outcome would likely trigger reinsurance recoveries for insurers.
Another major storm event struck the region in late July, with losses estimated at $5 billion or more. That event also threatened to rank among the top 10. Together, the two outbreaks could strain the insurance and reinsurance industry.
The full extent of the damage remains under assessment. The concentration of high winds in densely populated areas raises the likelihood of significant property and auto losses. Crossing the $5.1 billion threshold would mark the second time in two months that severe weather has delivered a multi-billion-dollar blow to the market.
Severe convective storms have accounted for a growing share of insured catastrophe losses in the U.S. Unlike hurricanes or earthquakes, these events can strike multiple states at once, increasing their financial impact. The frequency of billion-dollar storm events has risen in recent years, partly due to urban expansion into vulnerable areas and improved reporting of localized damage.
Insurers and reinsurers are monitoring claims data closely. If losses climb higher, the August outbreak could join a small but expensive group of storms that changed industry expectations about severe weather risk.
