This alert expired on 31 August 2026 at 01:45 UTC. It is kept here as a record.
No stronger detection stands among the 27 recorded within 20 km of this point since 3 April 2026 — 15 others scored the same. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 30 at 7:56PM CDT until August 30 at 8:45PM CDT by NWS Aberdeen SD
Nearby, since 3 April 2026
- August 31, 2026 · score 22 · 12.4 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 71 % 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 | 71% |
| Coordinates | 46.1060, -100.3529 |
| Nearest City | Bismarck (85 km) |
| Impact Tier | minor |
| Timestamp | 2026-08-31T00:56:00.000Z |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Campbell, SD; Corson, SD; Dewey, SD; Walworth, SD; Burleigh, ND; Emmons, ND; Morton, ND; Sioux, ND |
| Headline | Severe Thunderstorm Warning issued August 30 at 7:56PM 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 |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.d83d825bef0fdfebfa5461cbedc1068a6ef0dd8d.001.1","noaa_urn:oid:2.49.0.1.840.0.185f4af28a1f6f8b1cd84ad533fba21c5269af05.001.1"] |
| Spc ReportType | wind |
| Spc Speed | 65 |
| Spc Location | 8 N Selfridge |
| Spc County | Sioux |
| Spc State | ND |
| Spc Comments | Mesonet station TTKN8 Tatanka Prairie. (BIS) |
| Iem TypeSummary | G |
| Iem Magnitude | 65 |
| Iem Unit | MPH |
| Iem City | 8 N Selfridge |
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 Bismarck (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.