This alert expired on 18 July 2026 at 20:15 UTC. It is kept here as a record.
It is the 12th strongest of the 34 detections recorded within 20 km of this point since 17 March 2026. The last comparable one was on 5 July 2026. 11 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 18 at 4:02PM EDT until July 18 at 4:15PM EDT by NWS Mount Holly NJ
An estimated 71,326 people live within 50 km of this point.
Nearby, since 17 March 2026
- August 10, 2026 · score 39 · 8.8 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 39 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) | 39 / 100 |
| Our confidence | 80% |
| Coordinates | 37.9617, -77.9371 |
| Nearest City | Short Pump (45 km) |
| Population Exposed | 71.3K within 50 km |
| Impact Tier | significant |
| Date | 2026-07-18 — time not reported by the source |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.e562ce7efd55db5f352049b6d5097341 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Burlington, NJ; Anne Arundel, MD; Baltimore, MD; Howard, MD; Baltimore City, MD; Fairfax, VA; Loudoun, VA; Prince William, VA and 11 more areas |
| Headline | Severe Thunderstorm Warning issued July 18 at 4:02PM EDT until July 18 at 4:15PM EDT by NWS Mount Holly NJ |
| Expires | 2026-07-18T16:15:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | true |
| MergedCount | 16 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.e562ce7efd55db5f352049b6d5097341891ba45d.002.1","noaa_urn:oid:2.49.0.1.840.0.75a2f37ac62ff31b5babbd6370ff89c67c16ea5a.001.1","noaa_urn:oid:2.49.0.1.840.0.1a53fad4f7dff714b28feec7c26995aa212645ac.002.1","noaa_urn:oid:2.49.0.1.840.0.fd7ecd13a145b4fc8230a0bc92ee181fc04c0fa9.001.1","noaa_urn:oid:2.49.0.1.840.0.c23e3094f5f21160631d7559e408618a870c5899.002.1","noaa_urn:oid:2.49.0.1.840.0.6423d854b5591ccda52550a54aaa6aaad1e24dde.001.1","noaa_urn:oid:2.49.0.1.840.0.aba8cc5ffc86a9fcd7d8bd3535b983686366f987.001.1","noaa_urn:oid:2.49.0.1.840.0.6f09d7253eccad964e9d43727c902e8b58dd707a.001.1","noaa_urn:oid:2.49.0.1.840.0.4b7aa11745b750d8ec106cd410e8691124f56b55.001.1","noaa_urn:oid:2.49.0.1.840.0.05f65671e1811e3c7f5f8f75d7e1090ec9127067.001.1","noaa_urn:oid:2.49.0.1.840.0.9c6cecd202aeefe4015ea20acc8395ed35b4aac3.001.1","noaa_urn:oid:2.49.0.1.840.0.7f27fb1df7f787e0794514b01dfedd18929a6400.002.1","noaa_urn:oid:2.49.0.1.840.0.fe706b73f2feef4fc7c0ac3b8b31876eec962739.001.1","noaa_urn:oid:2.49.0.1.840.0.6a260d1737f7c0a4c1a3a404b6f3a3bdbe3c19c9.002.1","noaa_urn:oid:2.49.0.1.840.0.fc8f976d0fdc3db4e20c7cbe3fe13b00b97d6409.001.1","noaa_urn:oid:2.49.0.1.840.0.ddd84383277ba1673b9a07f24266aab4c772b509.001.1"] |
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 39/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.