Convective Chaos: The New Costliest Peril

Severe convective storms, once considered a “secondary peril,” are now driving the majority of insured catastrophe losses. In IASA’s March 18 webinar, Convective Chaos: The New Costliest Peril, Andrew Siffert, SVP and Senior Meteorologist at BMS Re, explored why this shift is happening and what it means for insurers.

Drawing on more than two decades of experience in catastrophe analytics and meteorology, Siffert unpacked how changing exposure patterns, evolving science, and updated catastrophe models are reshaping how the industry understands and manages risk. 

Watch Key Takeaways

Recap of the IASA Webinar held March 18, 2026

What’s Driving the Shift?

Over the past decade, severe convective storms, including hail, wind, and tornadoes, have accounted for nearly half of total insured catastrophe losses, surpassing hurricanes in both frequency and cumulative impact. But the increase in losses isn’t just about weather—it’s also about where and how we build. As populations expand and property values rise, more assets sit in harm’s way, amplifying the financial impact of even moderate events.

A New Kind of Risk Landscape

Rather than a few large, headline-grabbing catastrophes, insurers are facing a growing number of smaller, high-frequency events, sometimes called “kitty cats.” These events may not individually exceed $1B in losses, but collectively they are reshaping the risk landscape and challenging traditional modeling approaches. At the same time, advances in observational technology and field research like hail measurement campaigns and expanded weather sensor networks are improving the industry’s understanding of storm behavior while also revealing new complexities.

Looking Ahead

While early 2026 showed elevated storm activity, seasonal forecasting suggests a potential moderation as climate patterns shift toward El Niño conditions later in the year. Still, volatility remains the norm, and preparedness will be critical.