This alert expired on 12 June 2026 at 04:18 UTC. It is kept here as a record.
It is the 11th strongest of the 25 detections recorded within 20 km of this point since 18 April 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 June 11 at 11:08PM CDT until June 11 at 11:15PM CDT by NWS Norman OK
An estimated 224,596 people live within 50 km of this point.
Nearby, since 18 April 2026
- July 5, 2026 · score 43 · 3.4 km
- June 19, 2026 · score 43 · 14.8 km
- August 8, 2026 · score 43 · 19.8 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 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) | 37 / 100 |
| Our confidence | 80% |
| Coordinates | 34.2556, -98.2003 |
| Nearest City | Duncan (35 km) |
| Population Exposed | 224.6K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-06-12T04:08:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.229e7a7469685bb694b4bf23ddfe297b |
Score Breakdown
Technical Details
| Event | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Jefferson, OK; Stephens, OK; Cotton, OK |
| Headline | Severe Thunderstorm Warning issued June 11 at 11:08PM CDT until June 11 at 11:15PM CDT by NWS Norman OK |
| Expires | 2026-06-11T23:18:00-05:00 |
| SenderName | NWS Norman OK |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.229e7a7469685bb694b4bf23ddfe297b213f392e.001.1","noaa_urn:oid:2.49.0.1.840.0.bee60d430b15b839de369a6bb42eeb7e338969dc.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.
Want to know when something happens in this area?
Calamity.live data shows a weather event with CalamityScore 37/100 (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.