About our storm data
Our storm history pages and ZIP lookup summarize the National Weather Service's official storm records. Here's where they come from, how we count them, and what they can and can't tell you.
Where the data comes from
Every storm report comes from NOAA's Storm Events Database, the official record of storms kept by the National Oceanic and Atmospheric Administration's National Centers for Environmental Information. National Weather Service offices compile it from spotter, public, emergency manager, and media reports. It's public domain.
Our copy runs from 1950 through June 30, 2026. NOAA publishes each month's storms about 3 to 4 months later and sometimes revises older years; we reload the data every month. Town, county, and ZIP locations come from the U.S. Census Bureau's 2024 Gazetteer files and population estimates.
How we count
- We use three kinds of reports: hail, thunderstorm wind, and tornadoes. Before 1996, NOAA recorded only these three.
- A “hail day” is a day with at least one hail report. A “damaging wind day” is a day with thunderstorm winds of 58 mph or more, the National Weather Service's severe threshold.
- County pages count every report NOAA logged for the county. City pages and the ZIP lookup count reports within 10 miles of the city or ZIP code's center.
- “Last 10 years” means the 10 years before our latest data. Wind speeds are converted from knots to mph.
- We show short quotes from the National Weather Service's own storm descriptions, credited as “NWS.”
What the records can and can't tell you
- A report means hail or wind was observed near a place. It doesn't mean any particular home was damaged, and many storms that damage roofs are never reported.
- Reports depend on who was there to see them, so rural areas and older years have fewer.
- The records run a few months behind, so a storm from the past few months may not appear yet.
- Nothing here is insurance advice. Policies set their own rules for reporting damage.
The only way to know about your roof is to look. Look up your ZIP code, or send a photo from the home page for a Damage Score.
Reusing our storm statistics
The storm statistics on our storm pages (storm days, largest hail, dates, and counts) are licensed under Creative Commons Attribution 4.0 (CC BY 4.0). You can reuse them, including commercially, as long as you credit “DamageScore” and link to the page you used. The underlying NOAA records are public domain. This covers the storm statistics only, not the rest of our site.
Affiliation
DamageScore is not affiliated with NOAA, the National Weather Service, or the U.S. Census Bureau.