Right now
The most recent data we hold from NOAA arrived 2 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
2 other detections within 20 km in the last 24 hours, the nearest 10 km from here.
This alert expired on 20 September 2026 at 13:00 UTC. It is kept here as a record.
It is the 114th strongest of the 153 detections recorded within 20 km of this point since 11 March 2026. The last comparable one was on 15 September 2026. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued September 20 at 2:02AM CDT until September 20 at 8:00AM CDT by NWS Quad Cities IA IL
Urban PEI: 302,462 within a heuristic 50 km radius; not unique people.
Nearby, since 11 March 2026
- August 15, 2026 · score 37 · 7.8 km
- July 9, 2026 · score 43 · 11.2 km
- August 12, 2026 · score 43 · 11.9 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.
This is our versioned heuristic index, not source severity or a calibrated probability. Urban PEI does not count unique people.
Computed under scoring rules v5. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 37 / 100 |
| Legacy data-support index | 0.81/1 |
| Coordinates | 41.6349, -91.3246 |
| Nearest City | Iowa City (17 km) |
| Urban exposure index (PEI) | 302.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-20T07:02:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.f952cd75d64049b3d304e4fb9b2df5ca3da51779.001.1 |
Physical priority index · v5. Heuristic priority, not calibrated probability, predictive accuracy or damage. The legacy data-support index combines assigned source support and field availability. Urban PEI is distance-weighted and does not count unique people; zero does not establish that nobody is present. Model cards.
Source and revision timeline
Source: noaa. Occurrence: 2026-09-20T07:02:00.000Z.
First archived: 2026-09-20T07:05:28.947Z. Material modification: not recorded.
Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Benton, IA; Cedar, IA; Iowa, IA; Johnson, IA; Jones, IA; Linn, IA; Cedar, IA; Iowa, IA; Johnson, IA; Keokuk, IA; Louisa, IA; Muscatine, IA; Washington, IA; Clinton, IA; Muscatine, IA; Scott, IA; Bureau, IL; Henry, IL; Mercer, IL; Rock Island, IL; Whiteside, IL |
| Headline | Flash Flood Warning issued September 20 at 2:02AM CDT until September 20 at 8:00AM CDT by NWS Quad Cities IA IL |
| Expires | 2026-09-20T08:00:00-05:00 |
| SenderName | NWS Quad Cities IA IL |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.f952cd75d64049b3d304e4fb9b2df5ca3da51779.001.1","noaa_urn:oid:2.49.0.1.840.0.45fe6f13adc06894bca109974c0d521ff6186c1a.001.1","noaa_urn:oid:2.49.0.1.840.0.2407b6106c152666b5bdab0c6ef1dada9fd9ed21.001.1"] |
Safety Information
During flooding: never walk, swim, or drive through floodwaters. Six inches of moving water can knock you down, and one foot of water can sweep away a vehicle. Move to higher ground if waters rise. After flooding, avoid contact with floodwater which may contain sewage, chemicals, or debris. Follow local emergency service guidance.
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.
Review the area, threshold and delivery channel in your account.
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