This alert expired on 1 August 2026 at 00:45 UTC. It is kept here as a record.
No stronger detection stands among the 102 recorded within 20 km of this point since 11 March 2026 — 4 others scored the same. 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: Tornado Warning issued July 31 at 6:53PM CDT until July 31 at 7:45PM CDT by NWS Quad Cities IA IL
An estimated 278,494 people live within 50 km of this point.
Nearby, since 11 March 2026
- August 1, 2026 · score 67 · 2.4 km
- July 5, 2026 · score 43 · 7.9 km
- July 5, 2026 · score 43 · 10.9 km
How we know
Confirmed by 6 independent sources, including NOAA.
Our own score for this event is 67 out of 100, at 90 % 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 | 90% |
| Coordinates | 41.9600, -91.4740 |
| Nearest City | Marion (13 km) |
| Population Exposed | 278.5K within 50 km |
| Impact Tier | severe |
| Timestamp | 2026-07-31T23:53:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.c5bcb4fd61f624096bf9ed2365943acfd022ef8e.001.1 |
Score Breakdown
Technical Details
| Event | Tornado Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Linn, IA |
| Headline | Tornado Warning issued July 31 at 6:53PM CDT until July 31 at 7:45PM CDT by NWS Quad Cities IA IL |
| Expires | 2026-07-31T19:45:00-05:00 |
| SenderName | NWS Quad Cities IA IL |
| HasExactCoords | true |
| Iem TypeSummary | R |
| Iem Magnitude | 3.97 |
| Iem Unit | Inch |
| Iem City | 2 ESE Fairview |
| Iem County | Jones |
| Iem State | IA |
| Iem Wfo | DVN |
| Iem Remark | An additional 3.84 since the observation this morning. |
| MergedSources | [{"id":"iem_R_42.010_-91.660_1785533520000","source":"iem","severity":"low","severityValue":25,"timestamp":1785533520000,"latitude":42.01,"longitude":-91.66},{"id":"iem_R_42.050_-91.560_1785523020000","source":"iem","severity":"low","severityValue":25,"timestamp":1785523020000,"latitude":42.05,"longitude":-91.56},{"id":"iem_R_42.220_-91.440_1785534360000","source":"iem","severity":"low","severityValue":25,"timestamp":1785534360000,"latitude":42.22,"longitude":-91.44},{"id":"iem_R_41.970_-91.610_1785528240000","source":"iem","severity":"low","severityValue":25,"timestamp":1785528240000,"latitude":41.97,"longitude":-91.61},{"id":"iem_R_42.080_-91.300_1785535680000","source":"iem","severity":"low","severityValue":25,"timestamp":1785535680000,"latitude":42.08,"longitude":-91.3}] |
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 188 scientific monitoring sources.