Right now
The most recent data we hold from NOAA arrived 17 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 21 July 2026 at 16:30 UTC. It is kept here as a record.
No stronger detection stands among the 40 recorded within 20 km of this point since 17 March 2026 — 24 others scored the same. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 21 at 11:42AM EDT until July 21 at 12:30PM EDT by NWS Upton NY
An estimated 5,472,944 people live within 50 km of this point.
Nearby, since 17 March 2026
- July 21, 2026 · score 52 · 5.0 km
- May 20, 2026 · score 52 · 10.4 km
- July 21, 2026 · score 52 · 11.5 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 81 % 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 | 81% |
| Coordinates | 41.1063, -73.4287 |
| Nearest City | Norwalk (2 km) |
| Population Exposed | 5.5M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T15:42:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.1c0db7b2a15bbae40faeaf273e880022e8b56284.001.1 |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Fairfield, CT; Westchester, NY |
| Headline | Severe Thunderstorm Warning issued July 21 at 11:42AM EDT until July 21 at 12:30PM EDT by NWS Upton NY |
| Expires | 2026-07-21T12:30:00-04:00 |
| SenderName | NWS Upton NY |
| 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.
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