Reported by SPC today.
No stronger detection stands among the 34 recorded within 20 km of this point since 15 March 2026 — 3 others scored the same. Another comparable one was recorded here earlier the same day.
What the source measured
SPC reported: Wind 59 kt near 27 WNW Castle Rock, Butte, SD. (UNR)
How we know
One source: SPC. Not yet confirmed by a second, independent source.
Our own score for this event is 22 out of 100, at 47 % 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) | 22 / 100 |
| Our confidence | 47% |
| Coordinates | 45.1400, -103.9100 |
| Nearest City | Rapid City (130 km) |
| Impact Tier | minor |
| Timestamp | 2026-08-30T21:56:00.000Z |
| Source | https://www.spc.noaa.gov/climo/reports/today.html |
Score Breakdown
Technical Details
| ReportType | wind |
| Speed | 59 |
| Location | 27 WNW Castle Rock |
| County | Butte |
| State | SD |
| Comments | (UNR) |
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.
Calamity.live data shows a weather event with CalamityScore 22/100, near Rapid City (United States), based on data from spc. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.