This alert expired on 21 July 2026 at 19:45 UTC. It is kept here as a record.
It is the 57th strongest of the 100 detections recorded within 20 km of this point since 12 March 2026. Another comparable one was recorded here earlier the same day. 3 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 21 at 2:57PM EDT until July 21 at 3:45PM EDT by NWS Mount Holly NJ
An estimated 2,222,430 people live within 50 km of this point.
Nearby, since 12 March 2026
- July 6, 2026 · score 52 · 3.8 km
- June 12, 2026 · score 46 · 4.9 km
- July 27, 2026 · score 52 · 7.1 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 46 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) | 46 / 100 |
| Our confidence | 80% |
| Coordinates | 40.7410, -74.7511 |
| Nearest City | Basking Ridge (17 km) |
| Population Exposed | 2.2M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T18:57:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.864d166aec07032a33825e492cffd10d |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Hunterdon, NJ; Bucks, PA; Lehigh, PA; Northampton, PA; Bergen, NJ; Essex, NJ; Passaic, NJ |
| Headline | Severe Thunderstorm Warning issued July 21 at 2:57PM EDT until July 21 at 3:45PM EDT by NWS Mount Holly NJ |
| Expires | 2026-07-21T15:45:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.864d166aec07032a33825e492cffd10d216d1023.001.1","noaa_urn:oid:2.49.0.1.840.0.7739ac1f412b51c8d1bc4db879a4ce2a8184ea12.001.1"] |
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 46/100, near Basking Ridge (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.