This alert expired on 19 May 2026 at 22:30 UTC. It is kept here as a record.
It is the 2nd strongest of the 57 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 6 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued May 19 at 5:47PM EDT until May 19 at 6:30PM EDT by NWS Boston/Norton MA
An estimated 1,079,857 people live within 50 km of this point.
Nearby, since 16 March 2026
- August 13, 2026 · score 52 · 7.6 km
- August 8, 2026 · score 52 · 9.6 km
- May 19, 2026 · score 52 · 10.8 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 80 % 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 | 80% |
| Coordinates | 41.9982, -72.1362 |
| Nearest City | Southbridge (13 km) |
| Population Exposed | 1.1M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-19T21:47:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.383092258aac42ad05ce33a8ea509921 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Windham, CT; Middlesex, MA; Norfolk, MA; Worcester, MA; Providence, RI; Hartford, CT; Hampden, MA; Worcester, MA |
| Headline | Severe Thunderstorm Warning issued May 19 at 5:47PM EDT until May 19 at 6:30PM EDT by NWS Boston/Norton MA |
| Expires | 2026-05-19T18:30:00-04:00 |
| SenderName | NWS Boston/Norton MA |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.383092258aac42ad05ce33a8ea509921ff4a325e.001.1","noaa_urn:oid:2.49.0.1.840.0.80a0fbee17df9f2be4fe1fc103aaf0b9fb2c9d73.001.1","noaa_urn:oid:2.49.0.1.840.0.4379e0057eddd0134a92735f0f33972fe55463e4.002.1"] |
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.
Calamity.live data shows a weather event with CalamityScore 52/100, near Southbridge (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.