This alert expired on 17 May 2026 at 22:18 UTC. It is kept here as a record.
It is the 2nd strongest of the 24 detections recorded within 20 km of this point since 17 May 2026. Another comparable one was recorded here earlier the same day. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued May 17 at 5:09PM CDT until May 17 at 5:15PM CDT by NWS Green Bay WI
How we know
Confirmed by 7 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 | 44.3305, -86.8568 |
| Nearest City | Manitowoc (69 km) |
| Impact Tier | minor |
| Timestamp | 2026-05-17T22:09:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.b80fa721da2769747312d4dc31d55b22 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Sturgeon Bay to Two Rivers WI; Lake Michigan from Sturgeon Bay to Two Rivers WI 5NM offshore to Mid Lake; 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 |
| Headline | Special Marine Warning issued May 17 at 5:09PM CDT until May 17 at 5:15PM CDT by NWS Green Bay WI |
| Expires | 2026-05-17T17:18:00-05:00 |
| SenderName | NWS Green Bay WI |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.b80fa721da2769747312d4dc31d55b22c32a87ba.001.1","noaa_urn:oid:2.49.0.1.840.0.61f0495acc53f66a65c4b0200d63d7c553b162e3.001.1","noaa_urn:oid:2.49.0.1.840.0.63c6e916d983f91a9ced3324a8fde5ce26eb6761.001.1"] |
| Iem TypeSummary | D |
| Iem City | 1 NNE Two Rivers |
| Iem County | Manitowoc |
| Iem State | WI |
| Iem Wfo | GRB |
| Iem Remark | Downed trees and power lines along Sandy Bay Road just south of Lake Breeze Way. Time estimated from radar. |
| 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_44.160_-87.700_1779050820000","source":"iem","severity":"low","severityValue":25,"timestamp":1779050820000,"latitude":44.16,"longitude":-87.7},{"id":"iem_D_44.180_-87.580_1779051600000","source":"iem","severity":"low","severityValue":25,"timestamp":1779051600000,"latitude":44.18,"longitude":-87.58},{"id":"iem_R_44.150_-87.560_1779052980000","source":"iem","severity":"low","severityValue":25,"timestamp":1779052980000,"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},{"id":"iem_D_44.160_-87.550_1779051600000","source":"iem","severity":"low","severityValue":25,"timestamp":1779051600000,"latitude":44.16,"longitude":-87.55}] |
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.