Right now
The most recent data we hold from NOAA arrived 3 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 4 July 2026 at 23:45 UTC. It is kept here as a record.
No stronger detection stands among the 68 recorded within 20 km of this point since 16 March 2026 — 6 others scored the same. The last comparable one was on 19 May 2026.
What the source measured
NOAA reported: Special Marine Warning issued July 4 at 6:41PM EDT until July 4 at 7:45PM EDT by NWS Boston/Norton MA
An estimated 4,433,738 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 22, 2026 · score 52 · 12.7 km
- May 19, 2026 · score 52 · 16.5 km
- July 30, 2026 · score 52 · 17.7 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 52 out of 100, at 88 % 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 | 88% |
| Coordinates | 42.3330, -70.8860 |
| Nearest City | Winthrop (9 km) |
| Population Exposed | 4.4M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-04T22:41:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.cf90940f327273615d1edd57d8d80aa9d310c0c6.001.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Boston Harbor; Massachusetts Bay and Ipswich Bay |
| Headline | Special Marine Warning issued July 4 at 6:41PM EDT until July 4 at 7:45PM EDT by NWS Boston/Norton MA |
| Expires | 2026-07-04T19:45:00-04:00 |
| SenderName | NWS Boston/Norton MA |
| HasExactCoords | true |
| Iem TypeSummary | M |
| Iem Magnitude | 40 |
| Iem Unit | MPH |
| Iem City | 2 ENE Ipswich |
| Iem County | ANZ251 |
| Iem State | MA |
| Iem Wfo | BOX |
| Iem Remark | Mesonet station on Little Neck. |
| MergedSources | [{"id":"iem_M_42.890_-70.810_1783190640000","source":"iem","severity":"low","severityValue":25,"timestamp":1783190640000,"latitude":42.89,"longitude":-70.81},{"id":"iem_M_42.660_-70.600_1783192140000","source":"iem","severity":"low","severityValue":25,"timestamp":1783192140000,"latitude":42.66,"longitude":-70.6},{"id":"iem_M_42.690_-70.800_1783191840000","source":"iem","severity":"low","severityValue":25,"timestamp":1783191840000,"latitude":42.69,"longitude":-70.8}] |
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 Winthrop?
Calamity.live data shows a weather event with CalamityScore 52/100, near Winthrop (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.