This alert expired on 21 June 2026 at 05:30 UTC. It is kept here as a record.
No stronger detection stands among the 12 recorded within 20 km of this point since 6 May 2026 — 5 others scored the same. Another comparable one was recorded here earlier the same day. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 20 at 10:58PM MDT until June 20 at 11:30PM MDT by NWS Denver CO
An estimated 151,929 people live within 50 km of this point.
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 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) | 43 / 100 |
| Our confidence | 91% |
| Coordinates | 40.3480, -104.4280 |
| Nearest City | Evans (22 km) |
| Population Exposed | 151.9K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-21T04:58:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.819d3b24d817067135a7a7f515e2e686 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Morgan, CO; Weld, CO; Weld, CO |
| Headline | Severe Thunderstorm Warning issued June 20 at 10:58PM MDT until June 20 at 11:30PM MDT by NWS Denver CO |
| Expires | 2026-06-20T23:30:00-06:00 |
| SenderName | NWS Denver CO |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.819d3b24d817067135a7a7f515e2e686d1fd9a84.001.1","noaa_urn:oid:2.49.0.1.840.0.27da35f3462731bbe50078c1f4665dfd11b65344.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 1.25 |
| Iem Unit | Inch |
| Iem City | 8 NE Grover |
| Iem County | Weld |
| Iem State | CO |
| Iem Wfo | BOU |
| Iem Remark | Report from mPING: Half Dollar (1.25 in.). |
| MergedSources | [{"id":"iem_H_40.920_-104.020_1782006840000","source":"iem","severity":"low","severityValue":25,"timestamp":1782006840000,"latitude":40.92,"longitude":-104.02},{"id":"iem_H_40.960_-104.120_1782008460000","source":"iem","severity":"low","severityValue":25,"timestamp":1782008460000,"latitude":40.96,"longitude":-104.12}] |
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 Evans?
Calamity.live data shows a weather event with CalamityScore 43/100, near Evans (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.