This alert expired on 21 July 2026 at 23:15 UTC. It is kept here as a record.
It is the 100th strongest of the 143 detections recorded within 20 km of this point since 12 March 2026. The last comparable one was on 18 July 2026. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 21 at 6:35PM EDT until July 21 at 7:15PM EDT by NWS Pittsburgh PA
An estimated 700,766 people live within 50 km of this point.
Nearby, since 12 March 2026
- August 10, 2026 · score 48 · 4.5 km
- July 18, 2026 · score 43 · 5.5 km
- August 28, 2026 · score 48 · 8.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 41 out of 100, at 79 % 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) | 41 / 100 |
| Our confidence | 79% |
| Coordinates | 39.2376, -77.7340 |
| Nearest City | Leesburg (20 km) |
| Population Exposed | 700.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T22:35:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.62e5d2b53001a6609ddeb2c96290081a |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Tucker, WV; Grant, WV; Hampshire, WV; Hardy, WV; Mineral, WV; Montgomery, MD; Loudoun, VA and 7 more areas |
| Headline | Severe Thunderstorm Warning issued July 21 at 6:35PM EDT until July 21 at 7:15PM EDT by NWS Pittsburgh PA |
| Expires | 2026-07-21T19:15:00-04:00 |
| SenderName | NWS Pittsburgh PA |
| HasExactCoords | true |
| MergedCount | 10 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.62e5d2b53001a6609ddeb2c96290081ad249a302.002.1","noaa_urn:oid:2.49.0.1.840.0.3fbe5766bb0d761fce9c76719178af2aadb730f2.001.1","noaa_urn:oid:2.49.0.1.840.0.10c99e6cc154c7bd27acfb44fe8bf62bfd57d61a.001.1","noaa_urn:oid:2.49.0.1.840.0.5bfece26d0e646182bac3c6d2f0f36796c6bc8dc.001.1","noaa_urn:oid:2.49.0.1.840.0.cf6fdd6187f5091d97303ba50ebd2b4a05ae8507.001.1","noaa_urn:oid:2.49.0.1.840.0.85da92bc6010e1c1a95e4c7649fdd75bf4a4cbfd.001.1","noaa_urn:oid:2.49.0.1.840.0.eea87d77975a5b1f7d19493a0a79c269fecb4a79.001.1","noaa_urn:oid:2.49.0.1.840.0.d57dcd5a50cfda703ca01dd916cead63f8eff512.002.1","noaa_urn:oid:2.49.0.1.840.0.70204ceaa6ddc755e7cb380318e61a8c4f206368.001.1","noaa_urn:oid:2.49.0.1.840.0.d3fe9c5cd1e0e3c7366fb91b26beb730c5f9098d.002.1"] |
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 41/100, near Leesburg (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.