Right now
The most recent data we hold from NOAA arrived 2 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 30 May 2026 at 21:15 UTC. It is kept here as a record.
It is the 21st strongest of the 90 detections recorded within 20 km of this point since 15 March 2026. The last comparable one was on 22 May 2026. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 30 at 2:41PM MDT until May 30 at 3:15PM MDT by NWS Cheyenne WY
Nearby, since 15 March 2026
- July 7, 2026 · score 22 · 19.7 km
- July 4, 2026 · score 22 · 20.5 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 16 out of 100, at 61 % 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) | 16 / 100 |
| Our confidence | 61% |
| Coordinates | 43.5375, -103.8035 |
| Nearest City | Rapid City (76 km) |
| Impact Tier | minor |
| Timestamp | 2026-05-30T20:41:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.47613d2ae000c97ff7bb111147aa9c39 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Niobrara, WY; Custer, SD; Fall River, SD; Dawes, NE and 1 more areas |
| Headline | Severe Thunderstorm Warning issued May 30 at 2:41PM MDT until May 30 at 3:15PM MDT by NWS Cheyenne WY |
| Expires | 2026-05-30T15:15:00-06:00 |
| SenderName | NWS Cheyenne WY |
| HasExactCoords | true |
| MergedCount | 4 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.47613d2ae000c97ff7bb111147aa9c3957fdcc92.002.1","noaa_urn:oid:2.49.0.1.840.0.35147cb45ca6619fa716ef25461cfefef286e909.001.1","noaa_urn:oid:2.49.0.1.840.0.e7130abb451ac09e5ce038406d2d58f9eaa16415.001.1","noaa_urn:oid:2.49.0.1.840.0.ead0948743cf941a40f2a775e65b0370f41777cf.001.1"] |
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.
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