This alert expired on 16 July 2026 at 21:45 UTC. It is kept here as a record.
No stronger detection stands among the 98 recorded within 20 km of this point since 17 March 2026 — 17 others scored the same. 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 July 16 at 4:58PM EDT until July 16 at 5:45PM EDT by NWS Boston/Norton MA
An estimated 1,413,481 people live within 50 km of this point.
Nearby, since 17 March 2026
- March 17, 2026 · score 52 · 11.1 km
- June 26, 2026 · score 52 · 11.4 km
- July 16, 2026 · score 52 · 11.7 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 52 out of 100, at 81 % 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) | 52 / 100 |
| Our confidence | 81% |
| Coordinates | 42.8844, -71.2797 |
| Nearest City | Derry Village (3 km) |
| Population Exposed | 1.4M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-16T20:58:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.0ca53203be445f5c967de837245e1ef6 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Essex, MA; Rockingham, NH; Cheshire, NH; Hillsborough, NH; Rockingham, NH |
| Headline | Severe Thunderstorm Warning issued July 16 at 4:58PM EDT until July 16 at 5:45PM EDT by NWS Boston/Norton MA |
| Expires | 2026-07-16T17:45:00-04:00 |
| SenderName | NWS Boston/Norton MA |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.0ca53203be445f5c967de837245e1ef6c6a7aa29.001.1","noaa_urn:oid:2.49.0.1.840.0.06713225756f3e99335b009d5b06a080247dabc8.001.1","noaa_urn:oid:2.49.0.1.840.0.11443bd519e9885d2e18bb051c42eeb2b7745822.001.1"] |
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.
Want to know when something happens near Derry Village?
Calamity.live data shows a weather event with CalamityScore 52/100, near Derry Village (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.