This alert expired on 30 August 2026 at 20:45 UTC. It is kept here as a record.
No stronger detection stands among the 10 recorded within 20 km of this point since 23 April 2026 — 5 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 2:05PM MDT until August 30 at 2:45PM MDT by NWS Billings MT
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 65 % 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 | 65% |
| Coordinates | 45.3722, -105.4069 |
| Nearest City | Gillette (121 km) |
| Impact Tier | minor |
| Timestamp | 2026-08-30T20:05:00.000Z |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Powder River, MT |
| Headline | Severe Thunderstorm Warning issued August 30 at 2:05PM MDT until August 30 at 2:45PM MDT by NWS Billings MT |
| Expires | 2026-08-30T14:45:00-06:00 |
| SenderName | NWS Billings MT |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.56db5cde64839cb7cf758ca295af34c049dc4565.001.1","noaa_urn:oid:2.49.0.1.840.0.767358f2b080fa1c1711831e0b747ee8d487cd1f.001.1"] |
| Spc ReportType | wind |
| Spc Speed | 65 |
| Spc Location | 10 NNW Sonnette |
| Spc County | Powder River |
| Spc State | MT |
| Spc Comments | Mesonet station MTHCD Home Creek Divide Us-212 Mp 81.5. (BYZ) |
| MergedSources | [{"id":"spc_wind_45.55_-105.89_4","source":"spc","severity":"medium","severityValue":45,"timestamp":1788118200000,"latitude":45.55,"longitude":-105.89}] |
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 Gillette (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.