Right now
The most recent data we hold from NOAA arrived 55 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 3 July 2026 at 07:00 UTC. It is kept here as a record.
It is the 59th strongest of the 232 detections recorded within 20 km of this point since 10 March 2026. The last comparable one was on 2 July 2026. 27 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued July 2 at 8:13PM CDT until July 3 at 2:00AM CDT by NWS Des Moines IA
Urban PEI: 107,805 within a heuristic 50 km radius; not unique people.
Nearby, since 10 March 2026
- September 6, 2026 · score 37 · 14.9 km
- September 2, 2026 · score 37 · 14.9 km
- September 1, 2026 · score 37 · 14.9 km
How we know
13 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 43 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) | 43 / 100 |
| Legacy data-support index | 0.89/1 |
| Coordinates | 42.1152, -93.1083 |
| Nearest City | Marshalltown (18 km) |
| Urban exposure index (PEI) | 107.8K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-03T01:13:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.f5123700ec86ffbf139a9a01cd6b2bdb |
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: 2026-07-03T01:13:00.000Z.
First archived: 2026-07-03T04:17:58.263Z. 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 | Polk, IA; Story, IA; Black Hawk, IA; Grundy, IA; Marshall, IA; Tama, IA |
| Headline | Flash Flood Warning issued July 2 at 8:13PM CDT until July 3 at 2:00AM CDT by NWS Des Moines IA |
| Expires | 2026-07-03T02:00:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.f5123700ec86ffbf139a9a01cd6b2bdb8d6fb977.001.1","noaa_urn:oid:2.49.0.1.840.0.cb75368546da3357a7106491aff4df42a0332904.001.1"] |
| Iem TypeSummary | H |
| Iem Magnitude | 1.5 |
| Iem Unit | Inch |
| Iem City | 3 NE Windsor Heights |
| Iem County | Polk |
| Iem State | IA |
| Iem Wfo | DMX |
| MergedSources | [{"id":"iem_R_42.400_-92.450_1783040220000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040220000,"latitude":42.4,"longitude":-92.45},{"id":"iem_R_42.360_-92.770_1783038180000","source":"iem","severity":"low","severityValue":25,"timestamp":1783038180000,"latitude":42.36,"longitude":-92.77},{"id":"iem_H_41.610_-93.690_1783027560000","source":"iem","severity":"low","severityValue":25,"timestamp":1783027560000,"latitude":41.61,"longitude":-93.69},{"id":"iem_R_42.300_-92.780_1783040160000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040160000,"latitude":42.3,"longitude":-92.78},{"id":"iem_H_41.630_-93.700_1783028100000","source":"iem","severity":"low","severityValue":25,"timestamp":1783028100000,"latitude":41.63,"longitude":-93.7},{"id":"iem_R_42.400_-92.460_1783040580000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040580000,"latitude":42.4,"longitude":-92.46},{"id":"iem_F_42.340_-92.650_1783037940000","source":"iem","severity":"low","severityValue":25,"timestamp":1783037940000,"latitude":42.34,"longitude":-92.65},{"id":"iem_H_41.640_-93.700_1783028220000","source":"iem","severity":"low","severityValue":25,"timestamp":1783028220000,"latitude":41.64,"longitude":-93.7},{"id":"iem_R_42.370_-92.670_1783040040000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040040000,"latitude":42.37,"longitude":-92.67},{"id":"iem_R_42.260_-92.690_1783040100000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040100000,"latitude":42.26,"longitude":-92.69},{"id":"iem_R_42.310_-92.590_1783040280000","source":"iem","severity":"low","severityValue":25,"timestamp":1783040280000,"latitude":42.31,"longitude":-92.59},{"id":"iem_H_41.640_-93.660_1783028400000","source":"iem","severity":"low","severityValue":25,"timestamp":1783028400000,"latitude":41.64,"longitude":-93.66}] |
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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