This alert expired on 3 September 2026 at 23:30 UTC. It is kept here as a record.
It is the 2nd strongest of the 71 detections recorded within 20 km of this point since 12 March 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Tornado Warning issued September 3 at 7:12PM EDT until September 3 at 7:30PM EDT by NWS Pittsburgh PA
An estimated 40,100 people live within 50 km of this point.
Nearby, since 12 March 2026
- June 22, 2026 · score 46 · 3.9 km
- June 22, 2026 · score 46 · 3.9 km
- August 6, 2026 · score 39 · 7.1 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 58 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 | Critical |
| Calamity Score (ours) | 58 / 100 |
| Our confidence | 91% |
| Coordinates | 40.0573, -79.3836 |
| Nearest City | Murrysville (49 km) |
| Population Exposed | 40.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-03T23:12:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.3d478b2ec0e785a08a718e2b2f847edb1859fff9.001.1 |
Score Breakdown
Technical Details
| Event | Tornado Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Fayette, PA |
| Headline | Tornado Warning issued September 3 at 7:12PM EDT until September 3 at 7:30PM EDT by NWS Pittsburgh PA |
| Expires | 2026-09-03T19:30:00-04:00 |
| SenderName | NWS Pittsburgh PA |
| HasExactCoords | true |
| Spc ReportType | wind |
| Spc Speed | UNK |
| Spc Location | Irwin |
| Spc County | Westmoreland |
| Spc State | PA |
| Spc Comments | Report of numerous trees down in Irwin... PA. Time estimated based on radar. (PBZ) |
| Iem TypeSummary | D |
| Iem City | Irwin |
| Iem County | Westmoreland |
| Iem State | PA |
| Iem Wfo | PBZ |
| Iem Remark | Report of numerous trees down in Irwin, PA. Time estimated based on radar. |
Safety Information
If a tornado warning is issued: go to a basement or an interior room on the lowest floor, away from windows. A vehicle and a mobile home are not shelter. Cover your head and neck. Wait for the official all-clear before going outside, and watch for downed power lines and gas leaks afterwards.
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 58/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.