This alert expired on 2 September 2026 at 20:30 UTC. It is kept here as a record.
It is the 14th strongest of the 20 detections recorded within 20 km of this point since 4 April 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 2 at 4:05PM EDT until September 2 at 4:30PM EDT by NWS Detroit/Pontiac MI
Nearby, since 4 April 2026
- July 21, 2026 · score 22 · 6.2 km
- May 18, 2026 · score 22 · 15.0 km
- May 17, 2026 · score 46 · 15.9 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 16 out of 100, at 61 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 16 / 100 |
| Our confidence | 61% |
| Coordinates | 43.5317, -82.7417 |
| Nearest City | Sarnia (67 km) |
| Impact Tier | minor |
| Timestamp | 2026-09-02T20:05:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.e2cfce01cbdca40ff02491055b5f9c1005e6397a.002.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Sanilac, MI |
| Headline | Severe Thunderstorm Warning issued September 2 at 4:05PM EDT until September 2 at 4:30PM EDT by NWS Detroit/Pontiac MI |
| Expires | 2026-09-02T16:30:00-04:00 |
| SenderName | NWS Detroit/Pontiac MI |
| HasExactCoords | true |
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 in this area?
Calamity.live data shows a weather event with CalamityScore 16/100 (Canada), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.