This alert expired on 31 August 2026 at 01:45 UTC. It is kept here as a record.
No stronger detection stands among the 37 recorded within 20 km of this point since 4 April 2026 — 24 others scored the same. The last comparable one was on 9 August 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 30 at 8:37PM CDT until August 30 at 8:45PM CDT by NWS Aberdeen SD
Nearby, since 4 April 2026
- August 9, 2026 · score 22 · 15.6 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 66 % 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 | 66% |
| Coordinates | 45.7500, -99.9171 |
| Nearest City | Aberdeen (116 km) |
| Impact Tier | minor |
| Timestamp | 2026-08-31T01:37:00.000Z |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Campbell, SD; Walworth, SD |
| Headline | Severe Thunderstorm Warning issued August 30 at 8:37PM CDT until August 30 at 8:45PM CDT by NWS Aberdeen SD |
| Expires | 2026-08-30T20:45:00-05:00 |
| SenderName | NWS Aberdeen SD |
| HasExactCoords | true |
| Spc ReportType | wind |
| Spc Speed | 60 |
| Spc Location | 3 NE Mobridge Municipal |
| Spc County | Walworth |
| Spc State | SD |
| Spc Comments | Spotter estimated 50-60 mph gusts. (ABR) |
| MergedSources | [{"id":"spc_wind_45.57_-100.37_99","source":"spc","severity":"medium","severityValue":45,"timestamp":1788139140000,"latitude":45.57,"longitude":-100.37}] |
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 Aberdeen (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.