This alert expired on 10 August 2026 at 06:34 UTC. It is kept here as a record.
It is the 17th strongest of the 55 detections recorded within 20 km of this point since 18 May 2026. Another comparable one was recorded here earlier the same day. 13 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 10 at 1:24AM CDT until August 10 at 1:30AM CDT by NWS Chicago IL
An estimated 31,459 people live within 50 km of this point.
Nearby, since 18 May 2026
- June 8, 2026 · score 34 · 8.5 km
- September 5, 2026 · score 16 · 20.2 km
- August 10, 2026 · score 22 · 21.2 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 34 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 34 / 100 |
| Our confidence | 80% |
| Coordinates | 42.0883, -86.8444 |
| Nearest City | Michigan City (42 km) |
| Population Exposed | 31.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-10T06:24:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.402a5729455da9fd3489cc6aebafb0bb |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Wilmette Harbor to Northerly Island IL; Northerly Island to Calumet Harbor IL; Calumet Harbor IL to Gary IN; Gary to Burns Harbor IN; Burns Harbor to Michigan City IN; Lake Michigan from Wilmette Harbor to Michigan City in 5NM offshore to Mid Lake; New Buffalo MI to St Joseph MI; Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to mid-line of lake.; St Joseph to South Haven MI; South Haven to Holland MI; Holland to Grand Haven MI; 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 |
| Headline | Special Marine Warning issued August 10 at 1:24AM CDT until August 10 at 1:30AM CDT by NWS Chicago IL |
| Expires | 2026-08-10T01:34:00-05:00 |
| SenderName | NWS Chicago IL |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.402a5729455da9fd3489cc6aebafb0bbf2dcdac7.001.1","noaa_urn:oid:2.49.0.1.840.0.8c3854da51c2f85258b120b57b94a3e68bf5a2f9.001.1","noaa_urn:oid:2.49.0.1.840.0.1dbba129ed78bfd2c319c246a469a77970314bcd.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 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 in this area?
Calamity.live data shows a weather event with CalamityScore 34/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.