This alert expired on 3 July 2026 at 15:30 UTC. It is kept here as a record.
It is the 2nd strongest of the 105 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 23 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued July 3 at 4:32AM CDT until July 3 at 10:30AM CDT by NWS Des Moines IA
An estimated 547,016 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 21, 2026 · score 48 · 1.5 km
- May 19, 2026 · score 48 · 9.5 km
- July 21, 2026 · score 48 · 9.6 km
How we know
Confirmed by 11 independent sources, including NOAA.
Our own score for this event is 48 out of 100, at 90 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
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) | 48 / 100 |
| Our confidence | 90% |
| Coordinates | 41.7477, -93.5243 |
| Nearest City | Ankeny (7 km) |
| Population Exposed | 547.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-03T09:32:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.d6b328781ae2ac9cb41a65224447184e |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Story, IA; Polk, IA |
| Headline | Flash Flood Warning issued July 3 at 4:32AM CDT until July 3 at 10:30AM CDT by NWS Des Moines IA |
| Expires | 2026-07-03T10:30:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.d6b328781ae2ac9cb41a65224447184ee7df5139.001.1","noaa_urn:oid:2.49.0.1.840.0.752bdff9c6e13f03b19819ed6606074f580a43b9.001.1"] |
| Iem TypeSummary | R |
| Iem Magnitude | 4.98 |
| Iem Unit | Inch |
| Iem City | 2 NNW Alleman |
| Iem County | Polk |
| Iem State | IA |
| Iem Wfo | DMX |
| Iem Remark | Iowa Flood Center gage near NW 2nd St at Alleman. |
| MergedSources | [{"id":"iem_E_41.790_-93.570_1783063320000","source":"iem","severity":"low","severityValue":25,"timestamp":1783063320000,"latitude":41.79,"longitude":-93.57},{"id":"iem_R_41.770_-93.590_1783058520000","source":"iem","severity":"low","severityValue":25,"timestamp":1783058520000,"latitude":41.77,"longitude":-93.59},{"id":"iem_E_41.810_-93.580_1783067400000","source":"iem","severity":"low","severityValue":25,"timestamp":1783067400000,"latitude":41.81,"longitude":-93.58},{"id":"iem_R_41.900_-93.530_1783053780000","source":"iem","severity":"low","severityValue":25,"timestamp":1783053780000,"latitude":41.9,"longitude":-93.53},{"id":"iem_R_41.750_-93.620_1783058160000","source":"iem","severity":"low","severityValue":25,"timestamp":1783058160000,"latitude":41.75,"longitude":-93.62},{"id":"iem_R_41.830_-93.540_1783053900000","source":"iem","severity":"low","severityValue":25,"timestamp":1783053900000,"latitude":41.83,"longitude":-93.54},{"id":"iem_F_41.780_-93.570_1783061280000","source":"iem","severity":"low","severityValue":25,"timestamp":1783061280000,"latitude":41.78,"longitude":-93.57},{"id":"iem_R_41.820_-93.610_1783062600000","source":"iem","severity":"low","severityValue":25,"timestamp":1783062600000,"latitude":41.82,"longitude":-93.61},{"id":"iem_R_41.890_-93.400_1783053780000","source":"iem","severity":"low","severityValue":25,"timestamp":1783053780000,"latitude":41.89,"longitude":-93.4},{"id":"iem_R_41.840_-93.620_1783060320000","source":"iem","severity":"low","severityValue":25,"timestamp":1783060320000,"latitude":41.84,"longitude":-93.62}] |
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.
Want to know when something happens near Ankeny?
Calamity.live data shows a weather event with CalamityScore 48/100, near Ankeny (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.