Right now
The most recent data we hold from NOAA arrived 11 minutes 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 30 May 2026 at 05:00 UTC. It is kept here as a record.
It is one of only 3 we have recorded within 20 km of this point since 17 March 2026. The last comparable one was on 17 March 2026.
What the source measured
NOAA reported: Special Marine Warning issued May 30 at 12:34AM EDT until May 30 at 1:00AM EDT by NWS Boston/Norton MA
An estimated 73,064 people live within 50 km of this point.
Nearby, since 17 March 2026
- July 19, 2026 · score 22 · 17.0 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 79 % 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) | 39 / 100 |
| Our confidence | 79% |
| Coordinates | 41.2720, -70.3140 |
| Nearest City | Barnstable (48 km) |
| Population Exposed | 73.1K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-30T04:34:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.74a5afcef604e5d69e513cb5e0659058cae645c4.002.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Nantucket Sound; Coastal waters from Provincetown MA to Chatham MA to Nantucket MA out 20 NM; Coastal Waters extending out to 25 NM South of Marthas Vineyard and Nantucket; Coastal Waters from Montauk NY to Marthas Vineyard extending out to 20 NM South of Block Island |
| Headline | Special Marine Warning issued May 30 at 12:34AM EDT until May 30 at 1:00AM EDT by NWS Boston/Norton MA |
| Expires | 2026-05-30T01:00:00-04:00 |
| 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 in this area?
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 185 scientific monitoring sources.