This alert expired on 11 March 2026 at 05:00 UTC. It is kept here as a record.
It is the 95th strongest of the 126 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 10 March 2026. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Watch issued March 10 at 8:09PM EDT until March 11 at 1:00AM EDT by NWS Grand Rapids MI
Nearby, since 10 March 2026
- June 11, 2026 · score 16 · 0.0 km
- March 16, 2026 · score 22 · 0.0 km
- August 9, 2026 · score 22 · 0.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 16 out of 100, at 58 % 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) | 16 / 100 |
| Our confidence | 58% |
| Coordinates | 44.3000, -85.6000 |
| Nearest City | Traverse City (51 km) |
| Impact Tier | minor |
| Timestamp | 2026-03-11T00:09:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe-Thunderstorm-Watch_noaa_urn-oid-2_49_0_1_840_0_a2228adeba27e1a5a1706cfd92fb893a |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | St Joseph to South Haven MI; South Haven to Holland MI; Holland to Grand Haven MI; Grand Haven to Whitehall MI; Lake Michigan from Grand Haven to Whitehall MI 5NM offshore to Mid Lake; Lake Michigan from Holland to Grand Haven MI 5NM offshore to Mid Lake; Lake Michigan from South Haven to Holland MI 5NM offshore to Mid lake; Lake Michigan from St Joseph to South Haven MI 5NM offshore to Mid Lake; Allegan, MI; Barry, MI; Kalamazoo, MI; Kent, MI; Muskegon, MI; Ottawa, MI; Van Buren, MI; Calhoun, MI; Clinton, MI; Eaton, MI; Gratiot, MI; Ingham, MI; Ionia, MI; Jackson, MI; Montcalm, MI |
| Headline | Severe Thunderstorm Watch issued March 10 at 8:09PM EDT until March 11 at 1:00AM EDT by NWS Grand Rapids MI |
| Expires | 2026-03-11T01:00:00-04:00 |
| SenderName | NWS Grand Rapids MI |
| HasExactCoords | false |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.a2228adeba27e1a5a1706cfd92fb893a21e272a0.003.1","noaa_urn:oid:2.49.0.1.840.0.a2228adeba27e1a5a1706cfd92fb893a21e272a0.002.1","noaa_urn:oid:2.49.0.1.840.0.a2228adeba27e1a5a1706cfd92fb893a21e272a0.001.1"] |
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 16/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.