This alert expired on 2 September 2026 at 23:45 UTC. It is kept here as a record.
It is the 5th strongest of the 40 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 6:52PM EDT until September 2 at 7:45PM EDT by NWS Detroit/Pontiac MI
An estimated 101,455 people live within 50 km of this point.
Nearby, since 4 April 2026
- June 25, 2026 · score 43 · 3.2 km
- July 21, 2026 · score 43 · 5.4 km
- May 18, 2026 · score 43 · 7.3 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 49 out of 100, at 91 % 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 | High |
| Calamity Score (ours) | 49 / 100 |
| Our confidence | 91% |
| Coordinates | 43.0390, -82.5710 |
| Nearest City | Port Huron (14 km) |
| Population Exposed | 101.5K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-09-02T22:52:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.581b77324331afd8a88835aff0a07b5bbdf4be1f.002.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | St. Clair, MI |
| Headline | Severe Thunderstorm Warning issued September 2 at 6:52PM EDT until September 2 at 7:45PM EDT by NWS Detroit/Pontiac MI |
| Expires | 2026-09-02T19:45:00-04:00 |
| SenderName | NWS Detroit/Pontiac MI |
| HasExactCoords | true |
| Spc ReportType | hail |
| Spc Speed | 200 |
| Spc Location | 1 NW Capac |
| Spc County | St. Clair |
| Spc State | MI |
| Spc Comments | (DTX) |
| Iem TypeSummary | D |
| Iem City | Palms |
| Iem County | Sanilac |
| Iem State | MI |
| Iem Wfo | DTX |
| Iem Remark | Sanilac County Dispatch reported numerous calls related to tree damage and wires downed across the northern half of the county. |
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 near Port Huron?
Calamity.live data shows a weather event with CalamityScore 49/100, near Port Huron (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.