A storm swath is the geographic boundary of a hail or wind event — the exact area where damaging weather occurred — expressed as a polygon of GPS coordinates. When a hail storm passes through a metro area, it doesn't affect every neighborhood equally. HailTrace and other weather data providers map the precise path the storm took, including the specific hail size at every point within that path. The storm swath polygon is the geographic boundary of that impact area, and it is the key input that makes automated property targeting possible.
What the Swath Polygon Contains
A HailTrace storm swath polygon is a GeoJSON object — a series of latitude/longitude coordinate pairs that define the exact boundary of the storm's impact area. Within that boundary, HailTrace also provides hail size gradients: the outer edge of the swath where hail was minimal (0.75 to 1.0 inch), the middle zone (1.0 to 1.5 inch), and the core impact zone where the largest hail fell (1.5 inches or more). Each zone represents a different damage probability — a home in the core zone with a 1.75-inch hail event has a dramatically higher probability of roof damage than a home on the swath edge with 0.75-inch hail.
How the Swath Feeds Property Targeting
Once the swath polygon is defined, ATTOM Data's property API accepts it as a geo-query parameter and returns every property record within that boundary. This is the core of automated storm lead generation: instead of manually looking up addresses or buying a zip code list, the swath polygon precisely defines exactly which properties experienced the storm — to the address level. A 1,000-square-mile metro area contains millions of properties, but a typical storm swath might cover 20 to 50 square miles and affect 8,000 to 25,000 properties. The swath targeting ensures outreach is sent only to homeowners who actually had damaging weather at their address. The full swath-to-property pipeline is demonstrated at omnionlinestrategies.com/storm-lead-ai-machine.