Right now
The most recent data we hold from NOAA arrived 9 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 4 July 2026 at 11:36 UTC. It is kept here as a record.
No stronger detection stands among the 8 recorded within 20 km of this point since 18 May 2026 — 3 others scored the same. The last comparable one was on 2 July 2026. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued July 4 at 6:26AM CDT until July 4 at 6:30AM CDT by NWS Des Moines IA
Urban PEI: 89,709 within a heuristic 50 km radius; not unique people.
How we know
7 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 39 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 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) | 39 / 100 |
| Legacy data-support index | 0.91/1 |
| Coordinates | 42.1014, -93.9879 |
| Nearest City | Ames (31 km) |
| Urban exposure index (PEI) | 89.7K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-04T11:26:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.1e5389dc14d6e142f86c1e9a381f2d6c |
Physical priority index · v1. 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: 2026-07-04T11:26:00.000Z.
First archived: 2026-07-04T11:30:13.643Z. 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 | Marshall, IA; Story, IA; Calhoun, IA; Carroll, IA; Greene, IA; Sac, IA |
| Headline | Flash Flood Warning issued July 4 at 6:26AM CDT until July 4 at 6:30AM CDT by NWS Des Moines IA |
| Expires | 2026-07-04T06:36:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.1e5389dc14d6e142f86c1e9a381f2d6c8da260cc.001.1","noaa_urn:oid:2.49.0.1.840.0.696cfeac0e66e3ccf629b8ddc9d5109be3819d62.001.1"] |
| Iem TypeSummary | F |
| Iem City | 3 WNW Mitchellville |
| Iem County | Polk |
| Iem State | IA |
| Iem Wfo | DMX |
| Iem Remark | State radio relayed flooded interstate. |
| MergedSources | [{"id":"iem_G_41.540_-93.660_1783149540000","source":"iem","severity":"low","severityValue":25,"timestamp":1783149540000,"latitude":41.54,"longitude":-93.66},{"id":"iem_G_41.540_-93.660_1783149180000","source":"iem","severity":"low","severityValue":25,"timestamp":1783149180000,"latitude":41.54,"longitude":-93.66},{"id":"iem_F_42.050_-93.620_1783154040000","source":"iem","severity":"low","severityValue":25,"timestamp":1783154040000,"latitude":42.05,"longitude":-93.62},{"id":"iem_F_42.000_-93.570_1783153560000","source":"iem","severity":"low","severityValue":25,"timestamp":1783153560000,"latitude":42,"longitude":-93.57},{"id":"iem_F_42.020_-93.450_1783146000000","source":"iem","severity":"low","severityValue":25,"timestamp":1783146000000,"latitude":42.02,"longitude":-93.45},{"id":"iem_F_41.680_-93.400_1783153380000","source":"iem","severity":"low","severityValue":25,"timestamp":1783153380000,"latitude":41.68,"longitude":-93.4}] |
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.
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