This alert expired on 21 July 2026 at 21:30 UTC. It is kept here as a record.
It is the 24th strongest of the 44 detections recorded within 20 km of this point since 17 March 2026. The last comparable one was on 5 July 2026.
What the source measured
NOAA reported: Special Marine Warning issued July 21 at 4:48PM EDT until July 21 at 5:30PM EDT by NWS Upton NY
An estimated 306,255 people live within 50 km of this point.
Nearby, since 17 March 2026
- June 7, 2026 · score 43 · 15.7 km
- July 30, 2026 · score 43 · 16.1 km
- August 4, 2026 · score 48 · 24.1 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 37 out of 100, at 79 % 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) | 37 / 100 |
| Our confidence | 79% |
| Coordinates | 41.3717, -71.9383 |
| Nearest City | Westerly (9 km) |
| Population Exposed | 306.3K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T20:48:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Special Marine Warning_noaa_urn:oid:2.49.0.1.840.0.0b488ed169b3d682d97b06e2bfa04a24 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Long Island Sound East of New Haven CT/Port Jefferson NY to the Mouth of the Connecticut River; Long Island Sound West of New Haven CT/Port Jefferson NY; Cape Cod Bay; Nantucket Sound; Vineyard Sound; Buzzards Bay; Rhode Island Sound; Narragansett Bay; 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 July 21 at 4:48PM EDT until July 21 at 5:30PM EDT by NWS Upton NY |
| Expires | 2026-07-21T17:30:00-04:00 |
| SenderName | NWS Upton NY |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.0b488ed169b3d682d97b06e2bfa04a24219f96ac.001.1","noaa_urn:oid:2.49.0.1.840.0.7195651c72d716a15c37172bd0f697a01c5d8b3e.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 Westerly?
Calamity.live data shows a weather event with CalamityScore 37/100, near Westerly (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.