This alert expired on 12 June 2026 at 01:31 UTC. It is kept here as a record.
It is the 193rd strongest of the 269 detections recorded within 20 km of this point since 17 March 2026. The last comparable one was on 20 May 2026.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 11 at 9:23PM EDT until June 11 at 9:30PM EDT by NWS Baltimore MD/Washington DC
An estimated 2,824,017 people live within 50 km of this point.
Nearby, since 17 March 2026
- August 31, 2026 · score 48 · 8.9 km
- July 28, 2026 · score 48 · 9.1 km
- May 20, 2026 · score 52 · 9.6 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 46 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) | 46 / 100 |
| Our confidence | 80% |
| Coordinates | 39.9399, -75.6837 |
| Nearest City | West Chester (7 km) |
| Population Exposed | 2.8M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-12T01:23:00.000Z |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Anne Arundel, MD; Baltimore, MD; Calvert, MD; Cecil, MD; Charles, MD; Harford, MD; Prince Georges, MD; St. Marys, MD; Baltimore City, MD; King George, VA; Stafford, VA; City of Fredericksburg, VA; Baltimore, MD; Cecil, MD; Harford, MD; Monroe, PA and 4 more areas |
| Headline | Severe Thunderstorm Warning issued June 11 at 9:23PM EDT until June 11 at 9:30PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-06-11T21:31:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| MergedCount | 7 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.3394f828cc6ed05b513fecab6c3b0511a2c08185.001.1","noaa_urn:oid:2.49.0.1.840.0.2a5126d709e68ea3a1da4dbe9466775977b57d90.001.1","noaa_urn:oid:2.49.0.1.840.0.729e1e247ffdbb85fdeaea5f25f539f51f144131.001.1","noaa_urn:oid:2.49.0.1.840.0.39958b307014927b53eef518d5644cc78e2a19e7.001.1","noaa_urn:oid:2.49.0.1.840.0.bf74f0fd43e080e2f08faf8ab732a0e33f67c2d9.002.1","noaa_urn:oid:2.49.0.1.840.0.a61fcb5bc26bdaf273e0383f4f7470bc8b487f47.001.1","noaa_urn:oid:2.49.0.1.840.0.0705275bd4ce7a4eaed30d915b255ada7f646562.001.1"] |
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 46/100, near West Chester (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.