Right now
The most recent data we hold from NOAA arrived 3 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 20 May 2026 at 02:00 UTC. It is kept here as a record.
It is the 2nd strongest of the 120 detections recorded within 20 km of this point since 27 March 2026. Another comparable one was recorded here earlier the same day. 9 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued May 19 at 8:55PM EDT until May 19 at 10:00PM EDT by NWS Wilmington OH
An estimated 1,247,659 people live within 50 km of this point.
Nearby, since 27 March 2026
- September 5, 2026 · score 46 · 0.0 km
- September 4, 2026 · score 46 · 0.0 km
- September 3, 2026 · score 46 · 0.0 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 91 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 52 / 100 |
| Our confidence | 91% |
| Coordinates | 40.4000, -82.9000 |
| Nearest City | Delaware (18 km) |
| Population Exposed | 1.2M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-20T00:55:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Watch_noaa_urn:oid:2.49.0.1.840.0.76e6cb5f72a8726fda55b0d8272855d9 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | Butler, OH; Champaign, OH; Clark, OH; Greene, OH; Hamilton, OH; Montgomery, OH; Union, OH; Warren, OH; Clinton, OH; Delaware, OH; Fairfield, OH; Fayette, OH; Franklin, OH; Hocking, OH; Licking, OH; Madison, OH; Pickaway, OH |
| Headline | Severe Thunderstorm Watch issued May 19 at 8:55PM EDT until May 19 at 10:00PM EDT by NWS Wilmington OH |
| Expires | 2026-05-19T22:00:00-04:00 |
| SenderName | NWS Wilmington OH |
| HasExactCoords | false |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.76e6cb5f72a8726fda55b0d8272855d98942d663.002.1","noaa_urn:oid:2.49.0.1.840.0.76e6cb5f72a8726fda55b0d8272855d98942d663.003.1"] |
| Iem TypeSummary | D |
| Iem City | Choctaw Lake |
| Iem County | Madison |
| Iem State | OH |
| Iem Wfo | ILN |
| Iem Remark | Tree limbs down and minor shed damage. Time estimated from RADAR. |
| MergedSources | [{"id":"iem_D_40.590_-83.100_1779235320000","source":"iem","severity":"low","severityValue":25,"timestamp":1779235320000,"latitude":40.59,"longitude":-83.1},{"id":"iem_D_39.960_-83.490_1779237900000","source":"iem","severity":"low","severityValue":25,"timestamp":1779237900000,"latitude":39.96,"longitude":-83.49}] |
Safety Information
Always follow official guidance from your local emergency management agency. This platform provides scientific monitoring data and is not a substitute for official warnings. If you are in immediate danger, contact your local emergency number.
Series begins 8 March 2026. Comparisons refer to that period only. Collection gap: 14-26 August 2026.
This data is aggregated algorithmically from scientific sources. Not a replacement for official emergency warnings.
Want to know when something happens near Delaware?
Calamity.live data shows a weather event with CalamityScore 52/100, near Delaware (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.