This alert expired on 17 June 2026 at 01:45 UTC. It is kept here as a record.
It is the 6th strongest of the 20 detections recorded within 20 km of this point since 15 April 2026. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 16 at 9:20PM EDT until June 16 at 9:45PM EDT by NWS Grand Rapids MI
An estimated 190,839 people live within 50 km of this point.
Nearby, since 15 April 2026
- May 18, 2026 · score 43 · 6.0 km
- August 10, 2026 · score 43 · 6.9 km
- August 10, 2026 · score 43 · 12.6 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 37 out of 100, at 80 % 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) | 37 / 100 |
| Our confidence | 80% |
| Coordinates | 42.2500, -84.2100 |
| Nearest City | Jackson (16 km) |
| Population Exposed | 190.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-17T01:20:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.1c36de0526c35f1705b154469a5f88a0bb60461e.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Jackson, MI |
| Headline | Severe Thunderstorm Warning issued June 16 at 9:20PM EDT until June 16 at 9:45PM EDT by NWS Grand Rapids MI |
| Expires | 2026-06-16T21:45:00-04:00 |
| SenderName | NWS Grand Rapids 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 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.
Calamity.live data shows a weather event with CalamityScore 37/100, near Jackson (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.