This alert expired on 2 September 2026 at 05:15 UTC. It is kept here as a record.
No stronger detection stands among the 30 recorded within 20 km of this point since 15 March 2026 — 11 others scored the same. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 1 at 11:30PM CDT until September 2 at 12:15AM CDT by NWS Twin Cities/Chanhassen MN
An estimated 41,044 people live within 50 km of this point.
Nearby, since 15 March 2026
- June 30, 2026 · score 32 · 19.6 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 40 out of 100, at 92 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v4. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | High |
| Calamity Score (ours) | 40 / 100 |
| Our confidence | 92% |
| Coordinates | 43.9099, -94.1176 |
| Nearest City | Mankato (29 km) |
| Population Exposed | 41.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-02T04:30:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.eca0862e1a0541d92b2814b0af11f5723c803ddb.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Blue Earth, MN; Brown, MN; Faribault, MN; Martin, MN; Nicollet, MN; Watonwan, MN; Steele, MN; Waseca, MN |
| Headline | Severe Thunderstorm Warning issued September 1 at 11:30PM CDT until September 2 at 12:15AM CDT by NWS Twin Cities/Chanhassen MN |
| Expires | 2026-09-02T00:15:00-05:00 |
| SenderName | NWS Twin Cities/Chanhassen MN |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.eca0862e1a0541d92b2814b0af11f5723c803ddb.001.1","noaa_urn:oid:2.49.0.1.840.0.87304c003ec7d68596528f69fef2c2ad873db4c0.001.1"] |
| Spc ReportType | hail |
| Spc Speed | 175 |
| Spc Location | 2 W Delavan |
| Spc County | Faribault |
| Spc State | MN |
| Spc Comments | (MPX) |
| Iem TypeSummary | H |
| Iem Magnitude | 0.88 |
| Iem Unit | Inch |
| Iem City | 0 N Northrop |
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 Mankato?
Calamity.live data shows a weather event with CalamityScore 40/100, near Mankato (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.