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About the data

HailByDate is a free reference site that reorganises public U.S. storm reports so you can answer one question quickly: did it hail at this place, on or around this date?

Source

All storm reports come from the NOAA NCEI Storm Events Database, published by the U.S. National Centers for Environmental Information. We read the official bulk CSV releases at ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/. As a work of the U.S. federal government, that data is in the public domain.

Coverage

Currently 62,074 reports covering 2010–2026 for Texas, Oklahoma, Colorado — 392 counties. We include two event types: Hail and Thunderstorm Wind (severe wind, the NWS threshold being a 50-knot / 58 mph gust). Tornado, flood and winter events are out of scope. Data was last rebuilt on 2026-10-19; we refresh as NOAA publishes new monthly releases. More states are being added.

What we change

We do not add, estimate or interpolate any measurement. Our processing is limited to:

• Keeping county-level (CZ_TYPE = C) hail and thunderstorm-wind rows.
• Grouping rows by county and sorting by date.
• Deriving counts, per-year averages, monthly totals and maximums from the rows themselves.
• Converting knots to mph (× 1.15078) and labelling hail sizes with the common NWS comparison objects (a quarter is 1", a golf ball 1.75", a baseball 2.75").
• Shortening long report narratives for display.

Limits you should know about

• Reports, not measurements. Each row is something a person reported — a spotter, a trained observer, law enforcement, a damage survey, sometimes a social-media photo. Hail sizes are visual estimates.
• Population bias. Storms over towns and highways get reported; storms over empty rangeland often do not. A county with few reports is not necessarily a quiet county.
• Reporting has grown over time. Recent years look busier partly because more people report storms now. Read year-over-year trends with that in mind.
• County, not address. A report is tied to a county and a nearest-landmark bearing, not a street. A county-wide report does not mean hail fell on every property in it.
• Damage figures are preliminary. They are as filed at the time and are not revised in this archive.
• Gaps and revisions happen. NOAA corrects and backfills records; our snapshot may lag theirs.

Do not use this for

Insurance claims or disputes, legal filings, roof or structural assessments, engineering design, or anything where being wrong carries a cost. For those purposes get the official certified record from NOAA, or commission a site-specific hail report from a licensed provider. This site is general reference only and comes with no warranty.

Corrections

Spotted something wrong on a page? Tell us via contact and include the county and date. If the error is in the underlying NOAA record we will say so and point you to NOAA’s correction process; if it is ours, we will fix it on the next rebuild.