This alert expired on 13 May 2026 at 23:00 UTC. It is kept here as a record.
It is the 84th strongest of the 195 detections recorded within 20 km of this point since 17 March 2026. Another comparable one was recorded here earlier the same day. One more was recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 13 at 6:51PM EDT until May 13 at 7:00PM EDT by NWS Baltimore MD/Washington DC
An estimated 224,378 people live within 50 km of this point.
Nearby, since 17 March 2026
- May 18, 2026 · score 43 · 3.9 km
- August 27, 2026 · score 49 · 8.7 km
- August 27, 2026 · score 49 · 10.5 km
How we know
Confirmed by 2 independent sources, including NOAA.
Our own score for this event is 43 out of 100, at 86 % 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 | 86% |
| Coordinates | 39.3855, -77.9855 |
| Nearest City | Martinsburg (9 km) |
| Population Exposed | 224.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-13T22:51:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.5be4396735c2a60e3d26ad7caedda49dccd67432.002.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Clarke, VA; Frederick, VA; City of Winchester, VA; Berkeley, WV; Jefferson, WV |
| Headline | Severe Thunderstorm Warning issued May 13 at 6:51PM EDT until May 13 at 7:00PM EDT by NWS Baltimore MD/Washington DC |
| Expires | 2026-05-13T19:00:00-04:00 |
| SenderName | NWS Baltimore MD/Washington DC |
| HasExactCoords | true |
| Iem TypeSummary | G |
| Iem Magnitude | 61 |
| Iem Unit | mph |
| Iem City | 1 WSW Cross Junction |
| Iem County | Frederick |
| Iem State | VA |
| Iem Wfo | LWX |
| Iem Remark | Trained spotter measured wind gusts at 61 mph. |
| MergedSources | [{"id":"iem_G_39.320_-78.310_1778711580000","source":"iem","severity":"low","severityValue":25,"timestamp":1778711580000,"latitude":39.32,"longitude":-78.31}] |
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.
Want to know when something happens near Martinsburg?
Calamity.live data shows a weather event with CalamityScore 43/100, near Martinsburg (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 187 scientific monitoring sources.