This alert expired on 13 August 2026 at 22:30 UTC. It is kept here as a record.
It is the 4th strongest of the 224 detections recorded within 20 km of this point since 15 March 2026. 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 August 13 at 4:08PM MDT until August 13 at 4:30PM MDT by NWS Denver CO
An estimated 2,430,205 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 26, 2026 · score 52 · 2.5 km
- August 22, 2026 · score 52 · 7.7 km
- August 30, 2026 · score 52 · 8.3 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 84 % 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) | 52 / 100 |
| Our confidence | 84% |
| Coordinates | 39.6100, -104.7788 |
| Nearest City | Centennial (9 km) |
| Population Exposed | 2.4M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-13T22:08:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.fc9a23b7581c91ea02e1192d3aa11c552e121e83.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Western Arapahoe, CO; Douglas, CO |
| Headline | Severe Thunderstorm Warning issued August 13 at 4:08PM MDT until August 13 at 4:30PM MDT by NWS Denver CO |
| Expires | 2026-08-13T16:30:00-06:00 |
| SenderName | NWS Denver CO |
| HasExactCoords | true |
| Iem TypeSummary | H |
| Iem Magnitude | 1.25 |
| Iem Unit | Inch |
| Iem City | Centennial |
| Iem County | Arapahoe |
| Iem State | CO |
| Iem Wfo | BOU |
| Iem Remark | Report from mPING: Half Dollar (1.25 in.). |
| MergedSources | [{"id":"iem_H_39.590_-104.870_1786659000000","source":"iem","severity":"low","severityValue":25,"timestamp":1786659000000,"latitude":39.59,"longitude":-104.87}] |
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 Centennial?
Calamity.live data shows a weather event with CalamityScore 52/100, near Centennial (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.