This alert expired on 25 June 2026 at 22:30 UTC. It is kept here as a record.
No stronger detection stands among the 18 recorded within 20 km of this point since 4 April 2026 — 6 others scored the same. Another comparable one was recorded here earlier the same day. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 25 at 5:23PM EDT until June 25 at 6:30PM EDT by NWS Detroit/Pontiac MI
An estimated 101,455 people live within 50 km of this point.
Nearby, since 4 April 2026
- July 21, 2026 · score 43 · 3.6 km
- May 19, 2026 · score 43 · 8.1 km
- June 25, 2026 · score 43 · 9.5 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 86 % 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) | 43 / 100 |
| Our confidence | 86% |
| Coordinates | 43.0112, -82.5800 |
| Nearest City | Port Huron (14 km) |
| Population Exposed | 101.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-25T21:23:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.be88f12503e990dfd52795342eef9214536bdae1.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | St. Clair, MI |
| Headline | Severe Thunderstorm Warning issued June 25 at 5:23PM EDT until June 25 at 6:30PM EDT by NWS Detroit/Pontiac MI |
| Expires | 2026-06-25T18:30:00-04:00 |
| SenderName | NWS Detroit/Pontiac MI |
| HasExactCoords | true |
| Iem TypeSummary | H |
| Iem Magnitude | 0.5 |
| Iem Unit | inch |
| Iem City | 1 W Keewahdin |
| Iem County | St. Clair |
| Iem State | MI |
| Iem Wfo | DTX |
| MergedSources | [{"id":"iem_H_42.950_-82.560_1782415140000","source":"iem","severity":"low","severityValue":25,"timestamp":1782415140000,"latitude":42.95,"longitude":-82.56},{"id":"iem_H_43.040_-82.460_1782416100000","source":"iem","severity":"low","severityValue":25,"timestamp":1782416100000,"latitude":43.04,"longitude":-82.46}] |
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.
Want to know when something happens near Port Huron?
Calamity.live data shows a weather event with CalamityScore 43/100, near Port Huron (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 187 scientific monitoring sources.