This alert expired on 4 September 2026 at 01:00 UTC. It is kept here as a record.
It is the 13th strongest of the 41 detections recorded within 20 km of this point since 17 March 2026. The last comparable one was on 3 September 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued September 3 at 8:20PM EDT until September 3 at 9:00PM EDT by NWS Baltimore MD/Washington DC
An estimated 40,096 people live within 50 km of this point.
Nearby, since 17 March 2026
- August 11, 2026 · score 34 · 3.0 km
- June 22, 2026 · score 22 · 12.8 km
- June 22, 2026 · score 46 · 18.2 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 28 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 | Medium |
| Calamity Score (ours) | 28 / 100 |
| Our confidence | 91% |
| Coordinates | 39.9546, -79.1761 |
| Nearest City | Johnstown (47 km) |
| Population Exposed | 40.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-04T00:20:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.66b5005dc2ee24fe8d6ed95440d1cbcea0c3ed48.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Allegany, MD; Washington, MD; Morgan, WV; Bedford, PA; Blair, PA; Cambria, PA; Fulton, PA; Huntingdon, PA; Somerset, PA; Belmont, OH; Harrison, OH; Jefferson, OH; Washington, PA; Brooke, WV; Marshall, WV; Ohio, WV |
| Headline | Severe Thunderstorm Warning issued September 3 at 8:20PM EDT until September 3 at 9:00PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-09-03T21:00:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.66b5005dc2ee24fe8d6ed95440d1cbcea0c3ed48.001.1","noaa_urn:oid:2.49.0.1.840.0.d15a3524a0c1c942fa5e4ff2e17e62f18d677320.001.1","noaa_urn:oid:2.49.0.1.840.0.0e77841a795e43110270789708ba98ab03230eaa.002.1"] |
| Spc ReportType | wind |
| Spc Speed | UNK |
| Spc Location | 1 N Benson |
| Spc County | Somerset |
| Spc State | PA |
| Spc Comments | Tree down across Smith Street at the block of 158. (CTP) |
| Iem TypeSummary | D |
| Iem City | Mount Pleasant |
| Iem County | Westmoreland |
| Iem State | PA |
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.