This alert expired on 21 July 2026 at 23:37 UTC. It is kept here as a record.
It is the 6th strongest of the 25 detections recorded within 20 km of this point since 17 March 2026. Another comparable one was recorded here earlier the same day. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 21 at 7:27PM EDT until July 21 at 7:30PM EDT by NWS Buffalo NY
An estimated 370,832 people live within 50 km of this point.
Nearby, since 17 March 2026
- September 2, 2026 · score 37 · 9.2 km
- May 9, 2026 · score 43 · 14.1 km
- September 2, 2026 · score 37 · 22.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 37 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 37 / 100 |
| Our confidence | 80% |
| Coordinates | 42.9008, -77.6969 |
| Nearest City | Henrietta (19 km) |
| Population Exposed | 370.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T23:27:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.87e6018c9dd23ead334fde51b92abafe6122d176.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Livingston, NY; Monroe, NY; Ontario, NY |
| Headline | Severe Thunderstorm Warning issued July 21 at 7:27PM EDT until July 21 at 7:30PM EDT by NWS Buffalo NY |
| Expires | 2026-07-21T19:37:00-04:00 |
| SenderName | NWS Buffalo NY |
| HasExactCoords | true |
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 near Henrietta?
Calamity.live data shows a weather event with CalamityScore 37/100, near Henrietta (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.