This alert expired on 20 June 2026 at 01:15 UTC. It is kept here as a record.
It is the 5th strongest of the 53 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day. 10 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 19 at 7:51PM CDT until June 19 at 8:15PM CDT by NWS La Crosse WI
An estimated 94,872 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 10, 2026 · score 58 · 17.2 km
- August 9, 2026 · score 39 · 19.3 km
- June 5, 2026 · score 34 · 20.9 km
How we know
Confirmed by 5 independent sources, including NOAA.
Our own score for this event is 39 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) | 39 / 100 |
| Our confidence | 90% |
| Coordinates | 44.4608, -91.5323 |
| Nearest City | Eau Claire (39 km) |
| Population Exposed | 94.9K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-20T00:51:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.6d4edeff170375837a2d2165e39de9cf |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Buffalo, WI; Trempealeau, WI |
| Headline | Severe Thunderstorm Warning issued June 19 at 7:51PM CDT until June 19 at 8:15PM CDT by NWS La Crosse WI |
| Expires | 2026-06-19T20:15:00-05:00 |
| SenderName | NWS La Crosse WI |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.6d4edeff170375837a2d2165e39de9cfa4b8d0c2.001.1","noaa_urn:oid:2.49.0.1.840.0.b737300b5b5b333c974b7ff8d098a46dd2913ec7.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 1 |
| Iem Unit | Inch |
| Iem City | 2 ENE Osseo |
| Iem County | Trempealeau |
| Iem State | WI |
| Iem Wfo | ARX |
| Iem Remark | Report of quarter sized hail east of Osseo. |
| MergedSources | [{"id":"iem_D_44.980_-91.930_1781913300000","source":"iem","severity":"low","severityValue":25,"timestamp":1781913300000,"latitude":44.98,"longitude":-91.93},{"id":"iem_C_44.610_-91.190_1781913180000","source":"iem","severity":"low","severityValue":25,"timestamp":1781913180000,"latitude":44.61,"longitude":-91.19},{"id":"iem_H_44.760_-91.460_1781909640000","source":"iem","severity":"low","severityValue":25,"timestamp":1781909640000,"latitude":44.76,"longitude":-91.46},{"id":"iem_H_44.590_-91.170_1781912820000","source":"iem","severity":"low","severityValue":25,"timestamp":1781912820000,"latitude":44.59,"longitude":-91.17}] |
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 39/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.