This alert expired on 18 June 2026 at 13:00 UTC. It is kept here as a record.
It is the 5th strongest of the 59 detections recorded within 20 km of this point since 13 May 2026. The last comparable one was on 14 June 2026. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued June 18 at 8:42AM EDT until June 18 at 9:00AM EDT by NWS Baltimore MD/Washington DC
An estimated 42,354 people live within 50 km of this point.
Nearby, since 13 May 2026
- August 28, 2026 · score 34 · 13.6 km
- July 4, 2026 · score 34 · 13.9 km
- August 28, 2026 · score 34 · 18.8 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 34 out of 100, at 83 % 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 | 83% |
| Coordinates | 39.1967, -78.5067 |
| Nearest City | Winchester (30 km) |
| Population Exposed | 42.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-18T12:42:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.728ffda7664a4213d51ec4635d239ca11d789011.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Frederick, VA; Shenandoah, VA; Hampshire, WV; Hardy, WV |
| Headline | Severe Thunderstorm Warning issued June 18 at 8:42AM EDT until June 18 at 9:00AM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-06-18T09:00:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| Iem TypeSummary | G |
| Iem Magnitude | 51 |
| Iem Unit | MPH |
| Iem City | 8 SE Canaan Hgts |
| Iem County | Tucker |
| Iem State | WV |
| Iem Wfo | PBZ |
| MergedSources | [{"id":"iem_G_39.010_-79.320_1781784000000","source":"iem","severity":"low","severityValue":25,"timestamp":1781784000000,"latitude":39.01,"longitude":-79.32}] |
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 Winchester (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.