Right now
The most recent data we hold from NOAA arrived 16 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
One other detection within 20 km in the last 24 hours, 19 km from here.
This alert expired on 21 June 2026 at 21:45 UTC. It is kept here as a record.
It is the 18th strongest of the 57 detections recorded within 20 km of this point since 9 June 2026. Another comparable one was recorded here earlier the same day. 6 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 21 at 3:30PM MDT until June 21 at 3:45PM MDT by NWS North Platte NE
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 70 % 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) | 22 / 100 |
| Our confidence | 70% |
| Coordinates | 42.6600, -102.6057 |
| Nearest City | Rapid City (166 km) |
| Impact Tier | minor |
| Timestamp | 2026-06-21T21:30:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.2983734a25b9dc2d5a2742cc638942a91bd5ae07.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Sheridan, NE |
| Headline | Severe Thunderstorm Warning issued June 21 at 3:30PM MDT until June 21 at 3:45PM MDT by NWS North Platte NE |
| Expires | 2026-06-21T15:45:00-06:00 |
| SenderName | NWS North Platte NE |
| HasExactCoords | true |
| Iem TypeSummary | H |
| Iem Magnitude | 0.75 |
| Iem Unit | Inch |
| Iem City | 5 W Chadron |
| Iem County | Dawes |
| Iem State | NE |
| Iem Wfo | CYS |
| MergedSources | [{"id":"iem_H_42.800_-103.040_1782074880000","source":"iem","severity":"low","severityValue":25,"timestamp":1782074880000,"latitude":42.8,"longitude":-103.04},{"id":"iem_H_42.830_-103.090_1782074940000","source":"iem","severity":"low","severityValue":25,"timestamp":1782074940000,"latitude":42.83,"longitude":-103.09}] |
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 22/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.