This alert expired on 3 September 2026 at 19:00 UTC. It is kept here as a record.
No stronger detection stands among the 13 recorded within 20 km of this point since 3 April 2026 — one other scored the same. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 3 at 1:27PM CDT until September 3 at 2:00PM CDT by NWS Grand Forks ND
An estimated 57,011 people live within 50 km of this point.
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 45 out of 100, at 91 % 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) | 45 / 100 |
| Our confidence | 91% |
| Coordinates | 47.6438, -97.4548 |
| Nearest City | Grand Forks (45 km) |
| Population Exposed | 57.0K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-09-03T18:27:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.68bf5555f794fbb248291e8cd49844154bddc018.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Norman, MN; Polk, MN; Grand Forks, ND; Steele, ND; Traill, ND; Griggs, ND; Steele, ND |
| Headline | Severe Thunderstorm Warning issued September 3 at 1:27PM CDT until September 3 at 2:00PM CDT by NWS Grand Forks ND |
| Expires | 2026-09-03T14:00:00-05:00 |
| SenderName | NWS Grand Forks ND |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.68bf5555f794fbb248291e8cd49844154bddc018.001.1","noaa_urn:oid:2.49.0.1.840.0.8e7a9976aa1e4e23e59e567c4f717944d59311c5.001.1"] |
| Spc ReportType | hail |
| Spc Speed | 150 |
| Spc Location | Finley |
| Spc County | Steele |
| Spc State | ND |
| Spc Comments | (FGF) |
| Iem TypeSummary | H |
| Iem Magnitude | 1.5 |
| Iem Unit | Inch |
| Iem City | Finley |
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 45/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.