Reported by IEM today.
It is the 9th strongest of the 64 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day.
What the source measured
IEM reported: 5 hour rainfall total.
An estimated 1,211,333 people live within 50 km of this point.
Nearby, since 16 March 2026
- May 18, 2026 · score 52 · 6.5 km
- September 4, 2026 · score 46 · 17.6 km
- September 3, 2026 · score 76 · 18.3 km
How we know
Confirmed by 2 independent sources, including IEM.
Our own score for this event is 46 out of 100, at 77 % 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 | 77% |
| Coordinates | 42.2800, -83.7500 |
| Nearest City | Ann Arbor (1 km) |
| Population Exposed | 1.2M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-04T16:00:00.000Z |
| Source | https://mesonet.agron.iastate.edu/lsr/ |
Score Breakdown
Technical Details
| TypeSummary | R |
| Magnitude | 1.25 |
| Unit | Inch |
| City | Ann Arbor |
| County | Washtenaw |
| State | MI |
| Wfo | DTX |
| Remark | 5 hour rainfall total. |
| Google News RssFeed | weather |
| Google News SourceName | instagram.com |
| MergedSources | [{"id":"gnews_weather_496821_234","source":"google_news","severity":"medium","severityValue":40,"timestamp":1788558474000,"latitude":42.33,"longitude":-83.05}] |
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 Ann Arbor?
Calamity.live data shows a weather event with CalamityScore 46/100, near Ann Arbor (United States), based on data from iem. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.