This alert expired on 17 May 2026 at 21:15 UTC. It is kept here as a record.
No stronger detection stands among the 48 recorded within 20 km of this point since 15 March 2026 — 4 others scored the same. Another comparable one was recorded here earlier the same day. 8 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 17 at 3:57PM CDT until May 17 at 4:15PM CDT by NWS Green Bay WI
An estimated 244,231 people live within 50 km of this point.
Nearby, since 15 March 2026
- July 2, 2026 · score 43 · 4.6 km
- September 2, 2026 · score 37 · 8.4 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 84 % 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) | 43 / 100 |
| Our confidence | 84% |
| Coordinates | 44.1800, -87.6300 |
| Nearest City | Manitowoc (10 km) |
| Population Exposed | 244.2K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-17T20:57:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.24086fe38f97d4022d9913ca1c5c158ef6dfcc60.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Manitowoc, WI |
| Headline | Severe Thunderstorm Warning issued May 17 at 3:57PM CDT until May 17 at 4:15PM CDT by NWS Green Bay WI |
| Expires | 2026-05-17T16:15:00-05:00 |
| SenderName | NWS Green Bay WI |
| HasExactCoords | true |
| Iem TypeSummary | D |
| Iem City | 1 N Howards Grove |
| Iem County | Sheboygan |
| Iem State | WI |
| Iem Wfo | MKX |
| Iem Remark | At 230pm, Law Enforcement reported ~4 telephone poles down near the intersection of County Hwy FF and State Hwy 42. Damage time estimated from radar (215pm). |
| MergedSources | [{"id":"iem_D_43.850_-87.820_1779045300000","source":"iem","severity":"low","severityValue":25,"timestamp":1779045300000,"latitude":43.85,"longitude":-87.82}] |
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 near Manitowoc?
Calamity.live data shows a weather event with CalamityScore 43/100, near Manitowoc (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.