This alert expired on 11 August 2026 at 13:00 UTC. It is kept here as a record.
No stronger detection stands among the 40 recorded within 20 km of this point since 10 March 2026 — 7 others scored the same. Another comparable one was recorded here earlier the same day. 14 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Tornado Warning issued August 11 at 7:15AM CDT until August 11 at 8:00AM CDT by NWS Quad Cities IA IL
An estimated 167,735 people live within 50 km of this point.
Nearby, since 10 March 2026
- June 29, 2026 · score 28 · 9.6 km
- March 11, 2026 · score 49 · 15.2 km
- March 10, 2026 · score 44 · 15.2 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 67 out of 100, at 81 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | critical |
| Calamity Score (ours) | 67 / 100 |
| Our confidence | 81% |
| Coordinates | 42.4100, -91.3960 |
| Nearest City | Marion (45 km) |
| Population Exposed | 167.7K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-08-11T12:15:00.000Z |
Score Breakdown
Technical Details
| Event | Tornado Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Buchanan, IA; Delaware, IA |
| Headline | Tornado Warning issued August 11 at 7:15AM CDT until August 11 at 8:00AM CDT by NWS Quad Cities IA IL |
| Expires | 2026-08-11T08:00:00-05:00 |
| SenderName | NWS Quad Cities IA IL |
| HasExactCoords | true |
Safety Information
If a tornado warning is issued: go to a basement or an interior room on the lowest floor, away from windows. A vehicle and a mobile home are not shelter. Cover your head and neck. Wait for the official all-clear before going outside, and watch for downed power lines and gas leaks afterwards.
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 67/100, near Marion (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 191 scientific monitoring sources.