Right now
The most recent data we hold from NOAA arrived 27 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 17 May 2026 at 22:30 UTC. It is kept here as a record.
It is the 2nd strongest of the 22 detections recorded within 20 km of this point since 17 May 2026. Another comparable one was recorded here earlier the same day. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued May 17 at 5:31PM EDT until May 17 at 6:30PM EDT by NWS Grand Rapids MI
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 22 out of 100, at 69 % 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) | 22 / 100 |
| Our confidence | 69% |
| Coordinates | 44.2843, -86.8938 |
| Nearest City | Manitowoc (65 km) |
| Impact Tier | minor |
| Timestamp | 2026-05-17T21:31:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.e65f348a589f496a430733ac7a6f5b79 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Pentwater to Manistee MI; Lake Michigan from Pentwater to Manistee MI 5NM offshore to Mid Lake; Manistee to Point Betsie MI; Lake Michigan from Point Betsie to Manistee MI 5NM offshore to Mid Lake; Sturgeon Bay to Two Rivers WI; Two Rivers to Sheboygan WI; Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to Mid Lake; Lake Michigan from Two Rivers to Sheboygan WI 5NM offshore to Mid Lake |
| Headline | Special Marine Warning issued May 17 at 5:31PM EDT until May 17 at 6:30PM EDT by NWS Grand Rapids MI |
| Expires | 2026-05-17T18:30:00-04:00 |
| SenderName | NWS Grand Rapids MI |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.e65f348a589f496a430733ac7a6f5b79d8612b44.001.1","noaa_urn:oid:2.49.0.1.840.0.63c6e916d983f91a9ced3324a8fde5ce26eb6761.001.1","noaa_urn:oid:2.49.0.1.840.0.eb4678391e48b0384ec4677587c8ed9f24bc7355.001.1"] |
| Iem TypeSummary | D |
| Iem City | 1 SW Shoto |
| Iem County | Manitowoc |
| Iem State | WI |
| Iem Wfo | GRB |
| Iem Remark | 3 to 4 trees downed along County Road B. |
| MergedSources | [{"id":"iem_D_44.150_-87.560_1779051360000","source":"iem","severity":"low","severityValue":25,"timestamp":1779051360000,"latitude":44.15,"longitude":-87.56},{"id":"iem_D_44.150_-87.660_1779051000000","source":"iem","severity":"low","severityValue":25,"timestamp":1779051000000,"latitude":44.15,"longitude":-87.66}] |
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 22/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.