Why Severe Convective Storm Losses Now Depend More on Structure Than Geography
Three consecutive record years — $66B in insured losses in 2023, $59B in 2024, and $51B in 2025 — have reshaped how carriers need to think about severe convective storm risk. A new ZestyAI executive briefing on the 2026 SCS season shows the defining feature of these losses isn't storm frequency. It's accumulated structural damage. Within the same ZIP code, sometimes within the same complex, properties exposed to identical storms are producing materially different outcomes — and territory-level analysis is smoothing over the dispersion that actually drives the loss.
About this analysis. Findings are drawn from analysis of recent SCS seasons, IBHS research, and property-level storm segmentation across U.S. portfolios. The full briefing — 2026 Severe Convective Storm Season Overview — is a 16-page executive report covering loss dispersion patterns, peril-specific modeling, and what differentiated underwriting can actually move on portfolio performance.
Want the data? Download the full briefing → — 16 pages, immediate access.
What's driving three consecutive record SCS years?
Severe convective storm losses have accelerated steadily over the past five years, with sustained elevated activity beginning in 2020. The pattern of 2023, 2024, and 2025 — three of the highest insured-loss years on record back to back — isn't random. Underlying storm frequency has increased, but the cumulative effect on the building stock is the part most often underestimated. Each season of hail and wind exposure leaves a portfolio in a slightly more vulnerable state going into the next.
Why doesn't ZIP-code geography explain SCS loss patterns anymore?
Territory-level analysis smooths real differences between buildings. Two homes on the same street can face the same hailstorm and produce very different claims depending on roof age, roof material, prior exposure, defensible space, and the structural state of soft metals like gutters and vents. Blending those properties into a ZIP code average hides volatility that materially changes portfolio performance under stress.
That's the structural-not-geographic shift. Identical storms produce different outcomes because the structures aren't identical — and territory-level segmentation can't see it.
How does accumulated structural damage compound SCS risk?
This is the part of the story regulators and reinsurers are starting to focus on. Small hail events and ongoing weathering degrade roofing systems over time, even when no individual storm triggers a claim. Each marginal event leaves the roof slightly more vulnerable. Over a multi-year SCS cycle, the portfolios most exposed to losses are often the ones that quietly accumulated the most undamaged-but-degraded properties through prior seasons.
The implication is that a portfolio's SCS risk profile in 2026 isn't fully captured by its 2025 loss experience. The risk that didn't claim is still on the books.
Why does peril-specific modeling matter for hail and wind?
Hail, wind, and recurring micro-exposure don't behave the same way within an SCS footprint, even when they're all grouped under the same broad peril category. Hail damage concentrates in dense, often spatially clustered loss events. Straight-line wind produces a different damage signature. Recurring small-hail exposure compounds slowly across seasons. Modeling all three as a single SCS exposure obscures the separation that property-level intelligence can actually pick up — and that differentiated underwriting can actually act on.
What can property-level segmentation actually change?
In a Texas retrospective covered in the briefing, targeted underwriting actions informed by property-level segmentation would have reduced modeled loss cost by 48%. That's the magnitude of separation hiding inside portfolios that look uniform at the territory level. It's also what makes the 2026 question simpler than it sounds: not whether storms will develop, but whether the portfolio is segmented precisely enough before they do.
Get the full briefing
2026 Severe Convective Storm Season Overview →
The executive briefing walks through the multi-year SCS loss pattern, how property-level segmentation separates loss outcomes within the same footprint, and the Texas retrospective showing what differentiated underwriting can move on portfolio performance.
