Data sources and licences
All data are works of the United States government and in the public domain. OpenFEMA data are used under the OpenFEMA terms and conditions. This site was built 30 Sep 2026; the OpenFEMA endpoints named in the footer were accessed on that date.
| Source | Used for | Version | Licence |
|---|---|---|---|
| NOAA NCEI Storm Events Database | Yearly details files, 1950 to present | through 30 Jun 2026 | US government work |
| OpenFEMA Disaster Declarations Summaries (v2) | County-level declaration rows since 1953 | refreshed 29 Sep 2026 | US government work; OpenFEMA terms |
| OpenFEMA NFIP Claims (v3, redacted) | Claims by ZIP, county and year of loss with paid amounts | as of 8 Sep 2026 | US government work; OpenFEMA terms |
| OpenFEMA NFIP Multiple Loss Properties (v1) | Repetitive-loss counts by ZIP and county | as of 2 Aug 2026 | US government work; OpenFEMA terms |
| OpenFEMA NFIP Residential Penetration Rates (v1) | Residential policies in force by county | as of 3 Aug 2026 | US government work; OpenFEMA terms |
| FEMA National Risk Index, county table | Ratings and expected annual loss (read from FEMA's ArcGIS feature service) | December 2025 release | US government work |
| NOAA NHC HURDAT2 | hurdat2-1851-2025-02272026.txt and hurdat2-nepac-1949-2025-02272026.txt | through the 2025 season | US government work |
| US Census Bureau | 2021 county population estimates, 2021 gazetteer (area, centre points), 2021 cartographic boundary file (20m) | 2021 vintage | US government work |
This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. County Hazards is not affiliated with or endorsed by NOAA, FEMA, the National Hurricane Center or the Census Bureau.
Reuse
Tables and figures on this site may be quoted with a link to the page. The underlying data are public domain and best obtained from the agencies directly at the links above.