This alert expired on 27 May 2026 at 22:30 UTC. It is kept here as a record.
It is the 4th strongest of the 79 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 15 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 27 at 5:21PM CDT until May 27 at 5:30PM CDT by NWS Green Bay WI
An estimated 117,284 people live within 50 km of this point.
Nearby, since 15 March 2026
- July 21, 2026 · score 67 · 0.9 km
- June 30, 2026 · score 43 · 11.0 km
- May 27, 2026 · score 43 · 11.1 km
How we know
Confirmed by 22 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 90 % 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 | 90% |
| Coordinates | 44.6980, -89.8270 |
| Nearest City | Marshfield (27 km) |
| Population Exposed | 117.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-27T22:21:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.6918911d2b92097d7196e13695191726 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Portage, WI; Marathon, WI |
| Headline | Severe Thunderstorm Warning issued May 27 at 5:21PM CDT until May 27 at 5:30PM CDT by NWS Green Bay WI |
| Expires | 2026-05-27T17:30:00-05:00 |
| SenderName | NWS Green Bay WI |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.6918911d2b92097d7196e1369519172658ccc44b.001.1","noaa_urn:oid:2.49.0.1.840.0.66da7a3dcf87a3cce012c753497decf266db5e2c.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 1.75 |
| Iem Unit | Inch |
| Iem City | 1 ESE Rib Mountain Stat |
| Iem County | Marathon |
| Iem State | WI |
| Iem Wfo | GRB |
| MergedSources | [{"id":"iem_D_44.930_-89.630_1779916560000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916560000,"latitude":44.93,"longitude":-89.63},{"id":"iem_H_44.850_-89.600_1779918660000","source":"iem","severity":"low","severityValue":25,"timestamp":1779918660000,"latitude":44.85,"longitude":-89.6},{"id":"iem_H_44.950_-89.620_1779916740000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916740000,"latitude":44.95,"longitude":-89.62},{"id":"iem_H_44.930_-89.680_1779916620000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916620000,"latitude":44.93,"longitude":-89.68},{"id":"iem_H_44.920_-89.620_1779916800000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916800000,"latitude":44.92,"longitude":-89.62},{"id":"iem_H_44.900_-89.710_1779916920000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916920000,"latitude":44.9,"longitude":-89.71},{"id":"iem_H_44.980_-89.670_1779916200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916200000,"latitude":44.98,"longitude":-89.67},{"id":"iem_H_44.890_-89.600_1779917100000","source":"iem","severity":"low","severityValue":25,"timestamp":1779917100000,"latitude":44.89,"longitude":-89.6},{"id":"iem_H_44.850_-89.620_1779917640000","source":"iem","severity":"low","severityValue":25,"timestamp":1779917640000,"latitude":44.85,"longitude":-89.62},{"id":"iem_H_44.960_-89.610_1779916800000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916800000,"latitude":44.96,"longitude":-89.61},{"id":"iem_H_44.840_-89.610_1779918360000","source":"iem","severity":"low","severityValue":25,"timestamp":1779918360000,"latitude":44.84,"longitude":-89.61},{"id":"iem_H_44.990_-89.630_1779916560000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916560000,"latitude":44.99,"longitude":-89.63},{"id":"iem_H_44.950_-89.720_1779916500000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916500000,"latitude":44.95,"longitude":-89.72},{"id":"iem_H_44.920_-89.660_1779917820000","source":"iem","severity":"low","severityValue":25,"timestamp":1779917820000,"latitude":44.92,"longitude":-89.66},{"id":"iem_H_44.850_-89.610_1779918480000","source":"iem","severity":"low","severityValue":25,"timestamp":1779918480000,"latitude":44.85,"longitude":-89.61},{"id":"iem_H_44.900_-89.700_1779917340000","source":"iem","severity":"low","severityValue":25,"timestamp":1779917340000,"latitude":44.9,"longitude":-89.7},{"id":"iem_H_44.960_-89.640_1779916320000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916320000,"latitude":44.96,"longitude":-89.64},{"id":"iem_H_44.960_-89.690_1779916740000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916740000,"latitude":44.96,"longitude":-89.69},{"id":"iem_H_44.950_-89.620_1779916560000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916560000,"latitude":44.95,"longitude":-89.62},{"id":"iem_G_44.780_-89.670_1779919140000","source":"iem","severity":"low","severityValue":25,"timestamp":1779919140000,"latitude":44.78,"longitude":-89.67},{"id":"iem_H_44.910_-89.650_1779916680000","source":"iem","severity":"low","severityValue":25,"timestamp":1779916680000,"latitude":44.91,"longitude":-89.65}] |
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 Marshfield?
Calamity.live data shows a weather event with CalamityScore 43/100, near Marshfield (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.