This alert is in force until 3 September 2026, 20:30 UTC.
It is the 27th strongest of the 57 detections recorded within 20 km of this point since 14 April 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Special Marine Warning issued September 3 at 2:51PM EDT until September 3 at 4:30PM EDT by NWS Detroit/Pontiac MI
An estimated 3,026,520 people live within 50 km of this point.
Nearby, since 14 April 2026
- June 14, 2026 · score 52 · 1.0 km
- September 3, 2026 · score 9 · 2.4 km
- July 3, 2026 · score 52 · 2.4 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 46 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 | Medium |
| Calamity Score (ours) | 46 / 100 |
| Our confidence | 91% |
| Coordinates | 42.3685, -82.8826 |
| Nearest City | Tecumseh (5 km) |
| Population Exposed | 3.0M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-03T18:51:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.ce190a5b0742a95e0236f59211515f85c09935e3.001.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | St. Clair River; Harbor Beach to Port Sanilac MI; Port Sanilac to Port Huron MI; Lake Huron from Harbor Beach to Port Sanilac 5NM Off Shore to US/Canadian border; Lake Huron from Port Sanilac to Port Huron 5NM Off Shore to US/Canadian border; Maumee Bay to Reno Beach OH; Reno Beach to The Islands OH; Detroit River Lt. to Maumee Bay OH to Reno Beach OH beyond 5NM offshoreline to US-Canadian border; Reno Beach to The Islands OH beyond 5NM off shoreline to US-Canadian border |
| Headline | Special Marine Warning issued September 3 at 2:51PM EDT until September 3 at 4:30PM EDT by NWS Detroit/Pontiac MI |
| Expires | 2026-09-03T16:30:00-04:00 |
| SenderName | NWS Detroit/Pontiac MI |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.ce190a5b0742a95e0236f59211515f85c09935e3.001.1","noaa_urn:oid:2.49.0.1.840.0.7f5ca1921ee629d4ae589112ed0afa4b01f44c8e.001.1"] |
| Spc ReportType | wind |
| Spc Speed | UNK |
| Spc Location | Rochester |
| Spc County | Oakland |
| Spc State | MI |
| Spc Comments | Multiple downed trees and wires around Rochester. (DTX) |
| Iem TypeSummary | D |
| Iem City | 2 E Auburn Hills |
| Iem County | Oakland |
| Iem State | MI |
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 Tecumseh?
Calamity.live data shows a weather event with CalamityScore 46/100, near Tecumseh (Canada), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.