What's in the arsenal
41M+ records, five public hail sources.
Address lookups and scores draw on NOAA Storm Events, NEXRAD SWDI radar and CoCoRaHS volunteer reports, plus the last 90 days of MRMS near the address. Counts for all five tables below refresh hourly directly from production.
Master totals by source
NEXRAD SWDI
radar_hailNOAA NEXRAD Level-III hail-signature records (nx3hail) via the Severe Weather Data Inventory. Each record is a radar algorithm's estimate of hail size, stored as NOAA publishes it.
2015 → present
8,827,462
records
NCEP MRMS
mrms_meshMulti-Radar Multi-Sensor MESH-MAX-1440min product. Operational hail-size estimates from the National Centers for Environmental Prediction.
Pulled every two hours, 2026 → present
31,919,130
records
NOAA Storm Events DB
storm_eventsVerified hail occurrences with NWS narrative text, magnitudes, and event identifiers. The carrier-grade ground-truth source.
2000 → NOAA's latest monthly release, usually a few months behind (all 50 states + territories)
308,727
records
CoCoRaHS
cocorahs_reportsCommunity Collaborative Rain, Hail and Snow Network — ground-truth reports from volunteer spotters.
2015 → present
25,867
records
SPC / local storm reports
hail_reportsStorm Prediction Center local storm reports — preliminary hail sightings filed by trained spotters, swept weekly nationwide into the arsenal (fifth table in the public total). Counted in the record total; not a scoring input.
weekly national sweep (rolling 30-day re-read)
1,685
records
Top hail states — NOAA Storm Events
State-level distribution of verified hail occurrences in the NOAA Storm Events database. All 50 states + territories are covered; the top 20 by event count are shown below. Severe (≥1.0″) counts are a subset of the total.
| # | State | Hail events | ≥1.0″ | Max size |
|---|---|---|---|---|
| 1 | Texas | 34,771 | 25,471 | 7.02″ |
| 2 | Kansas | 28,706 | 19,052 | 7.75″ |
| 3 | Nebraska | 18,600 | 13,173 | 7.00″ |
| 4 | Oklahoma | 17,150 | 11,405 | 6.00″ |
| 5 | Colorado | 15,490 | 10,898 | 5.25″ |
| 6 | Missouri | 15,286 | 9,475 | 6.00″ |
| 7 | South Dakota | 13,733 | 9,300 | 8.00″ |
| 8 | Iowa | 12,596 | 7,974 | 5.50″ |
| 9 | Minnesota | 12,060 | 7,220 | 6.00″ |
| 10 | Illinois | 9,768 | 5,857 | 6.60″ |
| 11 | Arkansas | 7,599 | 4,546 | 5.00″ |
| 12 | North Dakota | 7,476 | 4,996 | 5.00″ |
| 13 | Wisconsin | 7,355 | 4,346 | 5.50″ |
| 14 | North Carolina | 7,051 | 3,676 | 4.50″ |
| 15 | Ohio | 6,774 | 3,367 | 5.00″ |
| 16 | Montana | 6,518 | 4,524 | 4.50″ |
| 17 | Georgia | 5,800 | 3,222 | 4.25″ |
| 18 | Indiana | 5,780 | 3,465 | 4.50″ |
| 19 | Mississippi | 5,561 | 3,408 | 4.88″ |
| 20 | Alabama | 5,529 | 3,334 | 5.38″ |
Temporal coverage
NOAA Storm Events go back to 2000 (with earlier scattered records), and NOAA publishes them a few months after each storm. Our NEXRAD SWDI radar records start in January 2015. Live MRMS ingestion runs every two hours, so new radar hail usually appears within about two hours of a storm.
Year 2015
9,398
verified hail events
Year 2016
9,407
verified hail events
Year 2017
10,398
verified hail events
Year 2018
7,863
verified hail events
Year 2019
8,992
verified hail events
Year 2020
7,677
verified hail events
Year 2021
6,268
verified hail events
Year 2022
7,180
verified hail events
Year 2023
11,761
verified hail events
Year 2024
8,938
verified hail events
Year 2025
9,208
verified hail events
Year 2026
5,455
verified hail events
Shown: last 12 years of NOAA Storm Events. Complete 2000–present available via API at /v1/property/history. Per-source ingest cadence and freshness are documented at /status.
Source attribution
All HailScore data ingestion comes from publicly accessible sources: US government archives plus the CoCoRaHS volunteer observer network. No proprietary or unattributed data is incorporated.
- NOAA NCEI
- National Centers for Environmental Information. Storm Events Database + Severe Weather Data Inventory.
- ncdc.noaa.gov/stormevents
- NCEP MRMS
- National Centers for Environmental Prediction. Multi-Radar Multi-Sensor operational hail product.
- nssl.noaa.gov/projects/mrms
- NWS
- National Weather Service. Active Alerts API (warning polygons + VTEC strings).
- weather.gov/documentation/services-web-api
- SPC
- Storm Prediction Center. Local Storm Reports (preliminary spotter reports).
- spc.noaa.gov/climo/reports
- CoCoRaHS
- Community Collaborative Rain, Hail and Snow Network. Volunteer ground-truth reports.
- cocorahs.org
What we don't cover
Honest scope statement, not a marketing one.
- ·NOAA Storm Events pre-2000 is sparse (scattered records back to 1955 for some states). Modern ingestion starts at 2000 because that's when NOAA's electronic record-keeping became consistent.
- ·Radar-derived data starts in 2015, where our NEXRAD SWDI backfill begins. Older radar records exist in NOAA's archive but aren't loaded.
- ·Live MRMS data starts 2026 with our operational cutover. Historical MRMS (pre-2026) isn't backfilled; the SWDI archive serves the historical use case.
- ·NWS Alert + SPC LSR per-event citations are listed in the methodology as referenced sources, but per-event publisher identifiers are not yet exposed via the v1 API. Both are roadmap items.
- ·Non-hail perils (flood, fire) are out of scope. HailScore is a hail-specific product. Wind and tornado reports from the same NOAA Storm Events feed appear on the report for context only and do not feed the score.
- ·International addresses are out of scope. HailScore covers US addresses only (50 states + territories). Non-US queries fail at geocoding.
─── Maintained
Coverage counts on this page refresh hourly directly from the production database. For per-source ingest cadence and freshness see /status. For the methodology white paper see /methodology. For carrier API integration see /api or /for-carriers.
Source data is public US government records plus CoCoRaHS volunteer reports. HailScore's contribution is the ingestion pipeline, address-level spatial indexing, calibrated scoring, and API surface — none of which is incorporated by reference into the counts above.