This alert expired on 6 June 2026 at 21:15 UTC. It is kept here as a record.
It is the 20th strongest of the 34 detections recorded within 20 km of this point since 13 May 2026. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 6 at 4:51PM EDT until June 6 at 5:15PM EDT by NWS Baltimore MD/Washington DC
An estimated 39,834 people live within 50 km of this point.
Nearby, since 13 May 2026
- July 7, 2026 · score 39 · 22.7 km
- August 28, 2026 · score 39 · 24.4 km
- August 27, 2026 · score 39 · 24.4 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 34 out of 100, at 80 % 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) | 34 / 100 |
| Our confidence | 80% |
| Coordinates | 40.2084, -77.6279 |
| Nearest City | Chambersburg (30 km) |
| Population Exposed | 39.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-06T20:51:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.a3c7c38eb98c33b16fd10ec7c80cf09e |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Frederick, MD; Washington, MD; Frederick, VA; Berkeley, WV; Hampshire, WV; Jefferson, WV; Morgan, WV; Dauphin, PA; Juniata, PA; Northumberland, PA; Perry, PA; Snyder, PA; Allegany, MD; Washington, MD; Frederick, VA; Hampshire, WV; Mineral, WV; Morgan, WV and 4 more areas |
| Headline | Severe Thunderstorm Warning issued June 6 at 4:51PM EDT until June 6 at 5:15PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-06-06T17:15:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 7 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.a3c7c38eb98c33b16fd10ec7c80cf09ed9ec70c5.001.1","noaa_urn:oid:2.49.0.1.840.0.f9e99245bb1022a49b0d1dad0d86644a541fa88e.001.1","noaa_urn:oid:2.49.0.1.840.0.d10e25b25d94f4daefbf831e7b23ce1bc097d061.002.1","noaa_urn:oid:2.49.0.1.840.0.78537b097dabf6e3fb42cdfb1578dc30e040a861.001.1","noaa_urn:oid:2.49.0.1.840.0.8ce50d6c8b6f5ea0c562d9e9219ac2eca07fa0b6.001.1","noaa_urn:oid:2.49.0.1.840.0.8cb6f88dc961f98d78875db5d8fd4db2e54ad694.001.1","noaa_urn:oid:2.49.0.1.840.0.a0d568190669735c0a7074a1f5f9a3c58750d9f7.001.1"] |
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 34/100, near Chambersburg (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.