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Flood in Sioux County, Iowa
164 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.
NCEI notes that Storm Data is compiled from a variety of sources including the National Weather Service, other federal, state and local agencies, the media and the public; that property and crop damage figures are estimates; and that some events are recorded by NWS forecast zone rather than by county. FEMA notes that NFIP claim records are redacted and aggregated to protect the privacy of policyholders. Storm records through 30 Jun 2026.
Sioux County, Iowa, has 164 flood events in the NCEI record since 1950, with at least one in 22 different years.
June is the busiest month, with 47 of the recorded events. The last 20 years account for 151 events against 13 in the 20 years before, a change that reflects reporting practice as much as weather.
The county holds 2.2% of the 7,383 flood events recorded in Iowa; its 21.4 per 100 square miles compares with 13.2 statewide.
NCEI attributes 1 death in the county to floods and flash floods.
Compared with Iowa
| Measure | Sioux County | Iowa | US |
|---|---|---|---|
| Flood events since 1950 | 164 | 7,383 | 183,559 |
| Per 100 square miles | 21.4 | 13.2 | 5.2 |
| Per 10,000 residents | 45.7 | 23.1 | 5.5 |
| Deaths recorded | 1 | 18 | 2,961 |
| Busiest month | June | June | June |
By year
Seasonality
0Feb
2Mar
23Apr
17May
20Jun
47Jul
23Aug
11Sep
15Oct
6Nov
0Dec
0
Recorded events
All 164 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.
| Date | Event type | Magnitude | Property damage | Crop damage | Deaths | Injuries | Geography |
|---|---|---|---|---|---|---|---|
| 28 Jun 2026 | Flash Flood | — | — | — | — | — | County |
| 30 Jul 2025 | Flash Flood | — | — | — | — | — | County |
| 30 Jul 2025 | Flood | — | — | — | — | — | County |
| 29 Jul 2025 | Flash Flood | — | — | — | — | — | County |
| 29 Jul 2025 | Flash Flood | — | — | — | — | — | County |
| 2 Jun 2025 | Flash Flood | — | — | — | — | — | County |
| 2 Jun 2025 | Flood | — | — | — | — | — | County |
| 1 Jul 2024 | Flood | — | — | — | — | — | County |
| 22 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 21 Jun 2024 | Flood | — | — | — | — | — | County |
| 20 Jun 2024 | Flood | — | — | — | — | — | County |
| 20 Jun 2024 | Flood | — | $6.5M | — | 1 | — | County |
| 5 Aug 2023 | Flash Flood | — | — | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | — | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | $100K | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | $5K | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | $1.5M | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | — | — | — | — | County |
| 5 Aug 2023 | Flash Flood | — | — | — | — | — | County |
| 10 Apr 2023 | Flood | — | — | — | — | — | County |
| 21 Mar 2023 | Flood | — | — | — | — | — | County |
| 9 Jun 2020 | Flash Flood | — | $10K | — | — | — | County |
| 1 Apr 2020 | Flood | — | — | $40K | — | — | County |
| 29 Mar 2020 | Flood | — | — | — | — | — | County |
| 29 Mar 2020 | Flood | — | — | — | — | — | County |
| 29 Mar 2020 | Flood | — | — | — | — | — | County |
| 10 Mar 2020 | Flood | — | — | — | — | — | County |
| 3 Oct 2019 | Flood | — | $5K | — | — | — | County |
| 14 Sep 2019 | Flood | — | $10K | — | — | — | County |
| 12 Sep 2019 | Flood | — | $10K | — | — | — | County |
| 12 Sep 2019 | Flood | — | $5K | — | — | — | County |
| 12 Sep 2019 | Flood | — | $10K | — | — | — | County |
| 17 Jul 2019 | Flood | — | — | — | — | — | County |
| 17 Jul 2019 | Flood | — | — | — | — | — | County |
| 10 Jul 2019 | Flood | — | — | — | — | — | County |
| 10 Jul 2019 | Flood | — | — | — | — | — | County |
| 2 Jul 2019 | Flood | — | — | — | — | — | County |
| 2 Jul 2019 | Flood | — | — | — | — | — | County |
| 1 Jul 2019 | Flash Flood | — | — | $25K | — | — | County |
| 1 Jul 2019 | Flash Flood | — | $5K | — | — | — | County |
| 27 Jun 2019 | Flood | — | — | — | — | — | County |
| 1 Jun 2019 | Flood | — | — | $2.3M | — | — | County |
| 1 Jun 2019 | Flood | — | — | — | — | — | County |
| 1 Jun 2019 | Flood | — | — | — | — | — | County |
| 1 Jun 2019 | Flood | — | — | — | — | — | County |
| 28 May 2019 | Flood | — | — | — | — | — | County |
| 28 May 2019 | Flood | — | — | — | — | — | County |
| 27 May 2019 | Flood | — | — | — | — | — | County |
| 27 May 2019 | Flood | — | — | — | — | — | County |
| 1 May 2019 | Flood | — | — | — | — | — | County |
| 1 May 2019 | Flood | — | — | — | — | — | County |
| 1 May 2019 | Flood | — | — | — | — | — | County |
| 1 Apr 2019 | Flood | — | — | — | — | — | County |
| 1 Apr 2019 | Flood | — | — | — | — | — | County |
| 1 Apr 2019 | Flood | — | — | — | — | — | County |
| 14 Mar 2019 | Flood | — | — | — | — | — | County |
| 14 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | $610K | — | — | — | County |
| 11 Oct 2018 | Flood | — | — | — | — | — | County |
| 11 Oct 2018 | Flood | — | — | — | — | — | County |
| 10 Oct 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flash Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flash Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 20 Sep 2018 | Flood | — | — | — | — | — | County |
| 4 Jul 2018 | Flood | — | — | — | — | — | County |
| 1 Jul 2018 | Flood | — | — | — | — | — | County |
| 24 Jun 2018 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 2018 | Flood | — | — | — | — | — | County |
| 21 Jun 2018 | Flood | — | — | — | — | — | County |
| 21 Jun 2018 | Flood | — | — | — | — | — | County |
| 21 Jun 2018 | Flood | — | — | — | — | — | County |
| 21 Jun 2018 | Flood | — | — | — | — | — | County |
| 12 May 2018 | Flood | — | — | — | — | — | County |
| 1 May 2018 | Flood | — | — | — | — | — | County |
| 22 Apr 2018 | Flood | — | — | — | — | — | County |
| 21 Apr 2018 | Flood | — | — | — | — | — | County |
| 1 Apr 2018 | Flood | — | — | — | — | — | County |
| 24 Mar 2018 | Flood | — | — | — | — | — | County |
| 6 Mar 2018 | Flood | — | — | — | — | — | County |
| 1 May 2016 | Flood | — | — | — | — | — | County |
| 29 Apr 2016 | Flood | — | — | — | — | — | County |
| 26 Jun 2014 | Flash Flood | — | — | — | — | — | County |
| 17 Jun 2014 | Flood | — | — | — | — | — | County |
| 16 Jun 2014 | Flood | — | $50K | — | — | — | County |
| 16 Jun 2014 | Flood | — | $1.0M | — | — | — | County |
| 15 Jun 2014 | Flood | — | $500K | $500K | — | — | County |
| 27 May 2013 | Flash Flood | — | $50K | — | — | — | County |
| 26 May 2013 | Flood | — | — | — | — | — | County |
| 26 May 2013 | Flash Flood | — | — | — | — | — | County |
| 26 May 2013 | Flood | — | $50K | — | — | — | County |
| 28 May 2012 | Flood | — | — | — | — | — | County |
| 27 May 2012 | Flash Flood | — | — | — | — | — | County |
| 7 May 2012 | Flood | — | — | — | — | — | County |
| 1 Aug 2011 | Flood | — | — | — | — | — | County |
| 13 Jul 2011 | Flood | — | — | — | — | — | County |
| 1 Jun 2011 | Flood | — | — | — | — | — | County |
| 22 May 2011 | Flood | — | — | — | — | — | County |
| 1 Apr 2011 | Flood | — | — | — | — | — | County |
| 16 Mar 2011 | Flood | — | — | — | — | — | County |
| 18 Feb 2011 | Flood | — | — | — | — | — | County |
| 23 Oct 2010 | Flash Flood | — | — | — | — | — | County |
| 1 Oct 2010 | Flood | — | — | — | — | — | County |
| 24 Sep 2010 | Flood | — | — | — | — | — | County |
| 23 Sep 2010 | Flood | — | — | — | — | — | County |
| 10 Aug 2010 | Flood | — | — | — | — | — | County |
| 1 Aug 2010 | Flood | — | — | — | — | — | County |
| 30 Jul 2010 | Flash Flood | — | — | — | — | — | County |
| 30 Jul 2010 | Flash Flood | — | $50K | — | — | — | County |
| 23 Jul 2010 | Flood | — | — | — | — | — | County |
| 23 Jul 2010 | Flood | — | — | — | — | — | County |
| 22 Jul 2010 | Flash Flood | — | — | — | — | — | County |
| 26 Jun 2010 | Flash Flood | — | — | — | — | — | County |
| 23 Jun 2010 | Flood | — | — | — | — | — | County |
| 22 Jun 2010 | Flash Flood | — | — | — | — | — | County |
| 22 Jun 2010 | Flash Flood | — | — | — | — | — | County |
| 22 Jun 2010 | Flash Flood | — | — | — | — | — | County |
| 13 Jun 2010 | Flood | — | — | — | — | — | County |
| 24 Apr 2010 | Flash Flood | — | — | — | — | — | County |
| 1 Apr 2010 | Flood | — | — | — | — | — | County |
| 15 Mar 2010 | Flood | — | — | — | — | — | County |
| 13 Mar 2010 | Flood | — | — | — | — | — | County |
| 13 Mar 2010 | Flood | — | — | — | — | — | County |
| 11 Feb 2009 | Flood | — | — | — | — | — | County |
| 13 Jun 2008 | Flood | — | — | — | — | — | County |
| 5 Jun 2008 | Flood | — | — | — | — | — | County |
| 20 Aug 2007 | Flash Flood | — | — | — | — | — | County |
| 10 Jun 2007 | Flash Flood | — | — | — | — | — | County |
| 1 Apr 2007 | Flood | — | — | — | — | — | County |
| 31 Mar 2007 | Flash Flood | — | — | — | — | — | County |
| 12 Mar 2007 | Flood | — | — | — | — | — | County |
| 2 May 2006 | Flood | — | — | — | — | — | County |
| 8 Apr 2006 | Flood | — | — | — | — | — | County |
| 1 Apr 2006 | Flood | — | — | — | — | — | County |
| 13 Jun 2005 | Flash Flood | — | — | — | — | — | County |
| 5 Jun 2005 | Flash Flood | — | — | — | — | — | County |
| 24 Jul 2001 | Flash Flood | — | — | — | — | — | County |
| 13 Jun 2001 | Flood | — | — | — | — | — | Forecast zone |
| 1 Apr 2001 | Flood | — | — | — | — | — | Forecast zone |
| 20 Jul 1999 | Flash Flood | — | — | — | — | — | County |
| 1 May 1997 | Flood | — | — | — | — | — | Forecast zone |
| 1 Apr 1997 | Flood | — | — | — | — | — | Forecast zone |
| 12 Mar 1997 | Flood | — | — | — | — | — | Forecast zone |
| 19 Jun 1996 | Flood | — | $200K | $500K | — | — | Forecast zone |
Questions and answers
How many flood events has Sioux County had?
164 events in the NCEI Storm Events record between 1950 and 2026. Reporting of floods and flash floods became far more complete after 1996, so early decades undercount.
When was the last recorded flood event in Sioux County?
28 Jun 2026 (Flash Flood). Records reach NCEI about 120 days after the month ends.
What was the most damaging flood event recorded in Sioux County?
The flood of 20 Jun 2024, with property damage estimated by NCEI at $6.5M; 1 death recorded.
How does Sioux County compare with Iowa for flood?
21.4 events per 100 square miles against 13.2 statewide; the county holds 164 of the state's 7,383 recorded events.
Provenance
NOAA NCEI Storm Events Database, yearly details files through 30 Jun 2026, public domain. County-recorded events plus zone-recorded events whose forecast zone is named for the county (marked "Forecast zone"). Population and area from the US Census Bureau (2021). Built 1 Oct 2026. See the methodology, the Flood hub and the county page.