Right now
The most recent data we hold from NOAA arrived 1 minute ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 22 July 2026 at 21:30 UTC. It is kept here as a record.
No stronger detection stands among the 37 recorded within 20 km of this point since 16 March 2026 — 4 others scored the same. The last comparable one was on 4 July 2026.
What the source measured
NOAA reported: Special Marine Warning issued July 22 at 4:27PM EDT until July 22 at 5:30PM EDT by NWS Boston/Norton MA
An estimated 4,302,212 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 4, 2026 · score 52 · 12.7 km
- May 19, 2026 · score 52 · 16.8 km
- May 19, 2026 · score 52 · 19.4 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.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 52 / 100 |
| Our confidence | 81% |
| Coordinates | 42.4264, -70.7964 |
| Nearest City | Marblehead (10 km) |
| Population Exposed | 4.3M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-22T20:27:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.0dcd32aea1b4479f1f6e4d80b8bd5534c14737ec.001.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Boston Harbor; Coastal waters east of Ipswich Bay and the Stellwagen Bank National Marine Sanctuary; Massachusetts Bay and Ipswich Bay |
| Headline | Special Marine Warning issued July 22 at 4:27PM EDT until July 22 at 5:30PM EDT by NWS Boston/Norton MA |
| Expires | 2026-07-22T17:30:00-04:00 |
| SenderName | NWS Boston/Norton MA |
| HasExactCoords | true |
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 8 March 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 Marblehead?
Calamity.live data shows a weather event with CalamityScore 52/100, near Marblehead (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.