Right now
The most recent data we hold from NOAA arrived 3 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 18 May 2026 at 18:30 UTC. It is kept here as a record.
It is the 17th strongest of the 52 detections recorded within 20 km of this point since 18 May 2026.
What the source measured
NOAA reported: Special Marine Warning issued May 18 at 12:30PM EDT until May 18 at 2:30PM EDT by NWS Grand Rapids MI
An estimated 31,459 people live within 50 km of this point.
Nearby, since 18 May 2026
- August 10, 2026 · score 34 · 3.5 km
- June 8, 2026 · score 34 · 5.0 km
- August 10, 2026 · score 22 · 17.8 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 | 42.0918, -86.8869 |
| Nearest City | Michigan City (42 km) |
| Population Exposed | 31.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-18T16:30:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.2c35388502c0f9480cb0dfdccbbf290d |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | 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; New Buffalo MI to St Joseph MI; Michigan City IN to New Buffalo MI; Lake Michigan Michigan City IN to St. Joseph MI 5 NM offshore to mid-line of lake.; Winthrop Harbor to Wilmette Harbor IL; 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 Winthrop Harbor to Wilmette Harbor IL 5NM offshore to Mid Lake; Lake Michigan from Wilmette Harbor to Michigan City in 5NM offshore to Mid Lake |
| Headline | Special Marine Warning issued May 18 at 12:30PM EDT until May 18 at 2:30PM EDT by NWS Grand Rapids MI |
| Expires | 2026-05-18T14:30:00-04:00 |
| SenderName | NWS Grand Rapids MI |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.2c35388502c0f9480cb0dfdccbbf290d51a676ce.001.1","noaa_urn:oid:2.49.0.1.840.0.9c09acd13247425de3828f508e397963a6266548.001.1","noaa_urn:oid:2.49.0.1.840.0.03e506535187c138bb6e2a5b32fa511270ea1536.001.1"] |
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.