How we detect & score hail

StormyLeads turns public weather data into decision-grade hail intelligence for repair crews. This page documents where our data comes from, how we detect and rank hail, and — just as importantly — what our numbers are not.

Data sources

Our hail events are detected from public US government weather data, then de-duplicated, geocoded, and enriched. Primary sources:

NOAA Storm Prediction Center (SPC) — daily severe-weather (hail) reports.
Iowa Environmental Mesonet (IEM) — NWS Local Storm Reports feed.

We do not resell raw NOAA data; our value-add is near-real-time detection, ranking, and repair-market sizing on top of it.

Detection & freshness

New storm reports are ingested about every 15 minutes, so the public dataset typically lags real events by minutes to a couple of hours. Each event carries a peak hail size (in inches), a location, and a timestamp. Hail is measured by peak stone diameter: 1″ (quarter-size) is the conventional damage threshold; 2″+ routinely dents vehicles and damages roofs.

The public pages on this site intentionally lag live data by 15 days — real-time access is what a Watchtower subscription unlocks.

The Work Score (0–100)

Each storm gets a Work Score from 0 to 100 — a single number for “how much repair work is here.” It combines the storm's peak hail size, the size of the impacted footprint, and the density of repairable assets (vehicles, rooftops, businesses) inside that footprint. Bigger hail over a denser area scores higher. The score is multiplicative, so a severe storm over an empty area and a moderate storm over a dealership district are correctly separated.

Dollar repair-market value

Alongside the Work Score we estimate a repair-market dollar range for a storm: the count of repairable assets in the footprint multiplied by typical per-job values for the trade. It answers “is this storm worth the drive?” — not “what will this specific roof cost.”

What these numbers are not

Our outputs are decision-grade estimates to help crews prioritize where to go — they are not meteorologist-verified, claim-grade, or address-specific appraisals. For insurance-claim documentation, use a forensic hail-verification provider. We'd rather be transparent about that boundary than overstate precision.

Coverage

Our dataset spans the contiguous US from 2024 to today — 22,102 hail events across 49 states, all with a measured peak hail size. See the live national hail data and per-state breakdowns.

Published by the StormyLeads Data Team. Source data © NOAA / NWS (public domain); analysis © Fixster, Inc. d/b/a StormyLeads.