This alert expired on 3 September 2026 at 20:45 UTC. It is kept here as a record.
It is the 2nd strongest of the 29 detections recorded within 20 km of this point since 3 April 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 3 at 2:39PM CDT until September 3 at 3:45PM CDT by NWS Grand Forks ND
An estimated 57,011 people live within 50 km of this point.
Nearby, since 3 April 2026
- June 10, 2026 · score 46 · 9.6 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 32 out of 100, at 86 % 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 | Medium |
| Calamity Score (ours) | 32 / 100 |
| Our confidence | 86% |
| Coordinates | 47.6483, -96.5610 |
| Nearest City | Grand Forks (47 km) |
| Population Exposed | 57.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-03T19:39:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.9f03c49bddd597eab0e0e70aea65c32edfb7f1b3.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Mahnomen, MN; Marshall, MN; Norman, MN; Pennington, MN; Polk, MN; Red Lake, MN; Traill, ND; Cass, ND; Traill, ND |
| Headline | Severe Thunderstorm Warning issued September 3 at 2:39PM CDT until September 3 at 3:45PM CDT by NWS Grand Forks ND |
| Expires | 2026-09-03T15:45:00-05:00 |
| SenderName | NWS Grand Forks ND |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.9f03c49bddd597eab0e0e70aea65c32edfb7f1b3.001.1","noaa_urn:oid:2.49.0.1.840.0.101d77e064688da464ece193178008de3fd23adf.002.1"] |
| Spc ReportType | wind |
| Spc Speed | 60 |
| Spc Location | Warren |
| Spc County | Marshall |
| Spc State | MN |
| Spc Comments | Estimated winds up to 60mph with pea sized hail. (FGF) |
| MergedSources | [{"id":"spc_wind_47.97_-97.40_27","source":"spc","severity":"medium","severityValue":45,"timestamp":1788460560000,"latitude":47.97,"longitude":-97.4},{"id":"spc_wind_48.20_-96.77_32","source":"spc","severity":"medium","severityValue":45,"timestamp":1788462480000,"latitude":48.2,"longitude":-96.77}] |
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 32/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.