This alert expired on 4 September 2026 at 00:30 UTC. It is kept here as a record.
No stronger detection stands among the 43 recorded within 20 km of this point since 15 March 2026 — 9 others scored the same. The last comparable one was on 29 August 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 3 at 7:15PM CDT until September 3 at 7:30PM CDT by NWS Grand Forks ND
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 28 out of 100, at 71 % 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) | 28 / 100 |
| Our confidence | 71% |
| Coordinates | 46.3147, -96.2267 |
| Nearest City | Moorhead (74 km) |
| Impact Tier | minor |
| Timestamp | 2026-09-04T00:15:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.da91537d2a29edd7d5fddf12f1e1bc0c9000616a.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Otter Tail, MN; Wilkin, MN |
| Headline | Severe Thunderstorm Warning issued September 3 at 7:15PM CDT until September 3 at 7:30PM CDT by NWS Grand Forks ND |
| Expires | 2026-09-03T19:30:00-05:00 |
| SenderName | NWS Grand Forks ND |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.da91537d2a29edd7d5fddf12f1e1bc0c9000616a.001.1","noaa_urn:oid:2.49.0.1.840.0.f164a9a5f8852aae9e71d79c1fb855f4bdd633da.001.1"] |
| Spc ReportType | hail |
| Spc Speed | 230 |
| Spc Location | 3 WNW Elbow Lake |
| Spc County | Grant |
| Spc State | MN |
| Spc Comments | Broadcast media shared photo of hail stone estimated to be 2 to 2.5 inches in diameter near Tulaby Lake MN. Time estimated from radar. (FGF) |
| Iem TypeSummary | H |
| Iem Unit | Inch |
| Iem City | 3 WNW Elbow Lake |
| Iem County | Grant |
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 28/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.