This alert expired on 1 June 2026 at 20:15 UTC. It is kept here as a record.
It is the 3rd strongest of the 148 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 1 at 1:31PM MDT until June 1 at 2:15PM MDT by NWS Denver CO
An estimated 1,856,876 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 3, 2026 · score 46 · 3.2 km
- August 16, 2026 · score 52 · 10.2 km
- August 27, 2026 · score 58 · 10.6 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 52 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 52 / 100 |
| Our confidence | 80% |
| Coordinates | 39.3826, -104.7883 |
| Nearest City | Castle Rock (6 km) |
| Population Exposed | 1.9M within 50 km |
| Impact Tier | significant |
| Date | 2026-06-01 — time not reported by the source |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.aefcfc19e976e4eb5b2c495c8306ed84 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Douglas, CO; Elbert, CO; Western Arapahoe, CO; Denver, CO; Douglas, CO; Adams, CO; Western Arapahoe, CO; Denver, CO and 1 more areas |
| Headline | Severe Thunderstorm Warning issued June 1 at 1:31PM MDT until June 1 at 2:15PM MDT by NWS Denver CO |
| Expires | 2026-06-01T14:15:00-06:00 |
| SenderName | NWS Denver CO |
| HasExactCoords | true |
| MergedCount | 4 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.aefcfc19e976e4eb5b2c495c8306ed84c176b6af.001.1","noaa_urn:oid:2.49.0.1.840.0.df8eaa99f995f5cf822298a49e457a3f0a85a4a7.001.1","noaa_urn:oid:2.49.0.1.840.0.9cecbcea4172b03dfbbed6b9938c290b6c2799f4.001.1","noaa_urn:oid:2.49.0.1.840.0.e8fa97bcaec7ffb34b088a224c38a9a35f9d1bd0.001.1"] |
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 10 February 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 Castle Rock?
Calamity.live data shows a weather event with CalamityScore 52/100, near Castle Rock (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.