This alert expired on 13 August 2026 at 22:15 UTC. It is kept here as a record.
It is the 2nd strongest of the 36 detections recorded within 20 km of this point since 17 March 2026. Another comparable one was recorded here earlier the same day. 5 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued August 13 at 5:39PM EDT until August 13 at 6:15PM EDT by NWS Boston/Norton MA
An estimated 1,078,436 people live within 50 km of this point.
Nearby, since 17 March 2026
- June 18, 2026 · score 64 · 10.2 km
- August 13, 2026 · score 52 · 12.2 km
- May 19, 2026 · score 52 · 19.5 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 78 % 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 | 78% |
| Coordinates | 41.8617, -71.9883 |
| Nearest City | Killingly Center (10 km) |
| Population Exposed | 1.1M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-13T21:39:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.79d63e1367d93739371ab494661d2cbc0d3f7433.002.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Tolland, CT; Windham, CT |
| Headline | Severe Thunderstorm Warning issued August 13 at 5:39PM EDT until August 13 at 6:15PM EDT by NWS Boston/Norton MA |
| Expires | 2026-08-13T18:15:00-04:00 |
| 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 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 Killingly Center (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.