This alert expired on 10 August 2026 at 13:30 UTC. It is kept here as a record.
It is the 6th strongest of the 105 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 16 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 10 at 9:19AM EDT until August 10 at 9:30AM EDT by NWS State College PA
An estimated 282,952 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 9, 2026 · score 43 · 5.9 km
- August 7, 2026 · score 37 · 7.0 km
- July 4, 2026 · score 43 · 7.4 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 92 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 43 / 100 |
| Our confidence | 92% |
| Coordinates | 39.9356, -76.6222 |
| Nearest City | York (10 km) |
| Population Exposed | 283.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-10T13:19:00.000Z |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Lancaster, PA; York, PA |
| Headline | Severe Thunderstorm Warning issued August 10 at 9:19AM EDT until August 10 at 9:30AM EDT by NWS State College PA |
| Expires | 2026-08-10T09:30:00-04:00 |
| SenderName | NWS State College PA |
| HasExactCoords | true |
| Iem TypeSummary | D |
| Iem City | 1 N Mechanicsburg |
| Iem County | Cumberland |
| Iem State | PA |
| Iem Wfo | CTP |
| Iem Remark | Trees and wires down on North Walnut Street. |
| MergedSources | [{"id":"iem_D_40.260_-77.080_1786364280000","source":"iem","severity":"low","severityValue":25,"timestamp":1786364280000,"latitude":40.26,"longitude":-77.08},{"id":"iem_D_40.220_-77.010_1786364100000","source":"iem","severity":"low","severityValue":25,"timestamp":1786364100000,"latitude":40.22,"longitude":-77.01}] |
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 10 February 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.
Calamity.live data shows a weather event with CalamityScore 43/100, near York (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.