This alert expired on 21 July 2026 at 06:46 UTC. It is kept here as a record.
It is the 2nd strongest of the 106 detections recorded within 20 km of this point since 16 March 2026. 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: Flash Flood Warning issued July 21 at 1:36AM CDT until July 21 at 1:45AM CDT by NWS Des Moines IA
An estimated 547,016 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 3, 2026 · score 48 · 1.5 km
- July 3, 2026 · score 48 · 9.2 km
- July 21, 2026 · score 48 · 9.3 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 48 out of 100, at 81 % 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 | 81% |
| Coordinates | 41.7456, -93.5417 |
| Nearest City | Ankeny (6 km) |
| Population Exposed | 547.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T06:36:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.ce77f220e0c0106603e97528a2cba5eb |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Boone, IA; Jasper, IA; Marshall, IA; Polk, IA; Story, IA; Dallas, IA; Polk, IA; Jasper, IA; Polk, IA |
| Headline | Flash Flood Warning issued July 21 at 1:36AM CDT until July 21 at 1:45AM CDT by NWS Des Moines IA |
| Expires | 2026-07-21T01:46:00-05:00 |
| SenderName | NWS Des Moines IA |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.ce77f220e0c0106603e97528a2cba5ebf5f5a4be.001.1","noaa_urn:oid:2.49.0.1.840.0.12eb84be4d2fe10267e1a8488c8942df7d9c2e38.001.1","noaa_urn:oid:2.49.0.1.840.0.3a43b22aa06d1277c36f9c85cc405793735307fa.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.
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.