This alert expired on 2 September 2026 at 05:30 UTC. It is kept here as a record.
It is the 3rd strongest of the 30 detections recorded within 20 km of this point since 15 March 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 2 at 12:01AM CDT until September 2 at 12:30AM CDT by NWS La Crosse WI
An estimated 91,612 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 7, 2026 · score 39 · 3.2 km
- March 15, 2026 · score 45 · 6.8 km
- June 30, 2026 · score 32 · 10.1 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 45 out of 100, at 92 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | high |
| Calamity Score (ours) | 45 / 100 |
| Our confidence | 92% |
| Coordinates | 43.9501, -93.2228 |
| Nearest City | Owatonna (14 km) |
| Population Exposed | 91.6K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-09-02T05:01:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.47fdaf0f8f67a7275e755d0d7980318231f16ad5.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Winona, MN; Steele, MN; Waseca, MN; Blue Earth, MN; Brown, MN; Faribault, MN; Martin, MN; Nicollet, MN; Watonwan, MN |
| Headline | Severe Thunderstorm Warning issued September 2 at 12:01AM CDT until September 2 at 12:30AM CDT by NWS La Crosse WI |
| Expires | 2026-09-02T00:30:00-05:00 |
| SenderName | NWS La Crosse WI |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.47fdaf0f8f67a7275e755d0d7980318231f16ad5.001.1","noaa_urn:oid:2.49.0.1.840.0.b84a4b41afadea2bcff33691e4a17b0d42464c5b.001.1","noaa_urn:oid:2.49.0.1.840.0.eca0862e1a0541d92b2814b0af11f5723c803ddb.001.1"] |
| Spc ReportType | hail |
| Spc Speed | 100 |
| Spc Location | 3 S Waldorf |
| Spc County | Waseca |
| Spc State | MN |
| Spc Comments | quarter sized hail reported on spotter network. (MPX) |
| Iem TypeSummary | H |
| Iem Magnitude | 1.75 |
| Iem Unit | Inch |
| Iem City | 2 W Delavan |
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 10 February 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 Owatonna?
Calamity.live data shows a weather event with CalamityScore 45/100, near Owatonna (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.