This alert expired on 18 May 2026 at 13:00 UTC. It is kept here as a record.
No stronger detection stands among the 27 recorded within 20 km of this point since 15 March 2026 — 15 others scored the same. Another comparable one was recorded here earlier the same day. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 18 at 7:52AM CDT until May 18 at 8:00AM CDT by NWS St Louis MO
An estimated 17,759 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 8, 2026 · score 28 · 6.0 km
- June 19, 2026 · score 22 · 7.7 km
- June 8, 2026 · score 16 · 9.8 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 34 out of 100, at 80 % 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) | 34 / 100 |
| Our confidence | 80% |
| Coordinates | 39.3120, -90.5466 |
| Nearest City | Godfrey (50 km) |
| Population Exposed | 17.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-18T12:52:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.b969e5b6b52d10ef57d6ff0ddc482b61 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Greene, IL; Jersey, IL; Greene, IL |
| Headline | Severe Thunderstorm Warning issued May 18 at 7:52AM CDT until May 18 at 8:00AM CDT by NWS St Louis MO |
| Expires | 2026-05-18T08:00:00-05:00 |
| SenderName | NWS St Louis MO |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.b969e5b6b52d10ef57d6ff0ddc482b61aa5ba794.002.1","noaa_urn:oid:2.49.0.1.840.0.a37d84ee378c02af99469fbb86b1dc52414bc989.002.1"] |
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 in this area?
Calamity.live data shows a weather event with CalamityScore 34/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.