This alert expired on 18 July 2026 at 21:47 UTC. It is kept here as a record.
No stronger detection stands among the 29 recorded within 20 km of this point since 17 March 2026 — 10 others scored the same. Another comparable one was recorded here earlier the same day. 12 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 18 at 5:37PM EDT until July 18 at 5:45PM EDT by NWS Mount Holly NJ
An estimated 121,619 people live within 50 km of this point.
Nearby, since 17 March 2026
- July 7, 2026 · score 43 · 3.6 km
- July 21, 2026 · score 32 · 8.4 km
- June 22, 2026 · score 43 · 15.8 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 43 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) | 43 / 100 |
| Our confidence | 79% |
| Coordinates | 37.9680, -77.2402 |
| Nearest City | Mechanicsville (41 km) |
| Population Exposed | 121.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-18T21:37:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.e7c31db7d031574e4793c04e8b3bd0fc |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Caroline, MD; Talbot, MD; Essex, VA; Lancaster, VA; Northumberland, VA; Richmond, VA; Westmoreland, VA; Kent, DE; Sussex, DE; Caroline, MD; Queen Anne's, MD; Talbot, MD and 6 more areas |
| Headline | Severe Thunderstorm Warning issued July 18 at 5:37PM EDT until July 18 at 5:45PM EDT by NWS Mount Holly NJ |
| Expires | 2026-07-18T17:47:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | true |
| MergedCount | 9 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.e7c31db7d031574e4793c04e8b3bd0fca8bb6746.001.1","noaa_urn:oid:2.49.0.1.840.0.eeccdf3379f6c2789dd17612e5f5e19ed5c7e1cd.001.1","noaa_urn:oid:2.49.0.1.840.0.a115335455503480d20cfa1273b583a66f4b23ab.001.1","noaa_urn:oid:2.49.0.1.840.0.8746d54a68442f0c3371ef79f8aad4f3eee04c2f.001.1","noaa_urn:oid:2.49.0.1.840.0.ee8dfe4b0ad3bacb39a26c2344454fcbfbb5ef0c.001.1","noaa_urn:oid:2.49.0.1.840.0.05fff0826d87bb9b92770dc6ac05d4b125779784.001.1","noaa_urn:oid:2.49.0.1.840.0.79c9edb716823e5081cb71f4da0a83414e3ed8a4.002.1","noaa_urn:oid:2.49.0.1.840.0.721df68eec12773ca6fca8e543287d8798a4342f.001.1","noaa_urn:oid:2.49.0.1.840.0.336e1524321efa8ae8976b8a3ef7b936bca25ff2.001.1"] |
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 43/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.