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Flood in Harrison County, Iowa
31 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.
Harrison County, Iowa, has 31 flood events in the NCEI record since 1950, with at least one in 13 different years.
June is the busiest month, with 10 of the recorded events. The last 20 years account for 20 events against 11 in the 20 years before, a change that reflects reporting practice as much as weather.
The county holds 0.4% of the 7,383 flood events recorded in Iowa; its 4.4 per 100 square miles compares with 13.2 statewide.
Compared with Iowa
| Measure | Harrison County | Iowa | US |
|---|---|---|---|
| Flood events since 1950 | 31 | 7,383 | 183,559 |
| Per 100 square miles | 4.4 | 13.2 | 5.2 |
| Per 10,000 residents | 21.1 | 23.1 | 5.5 |
| Deaths recorded | 0 | 18 | 2,961 |
| Busiest month | June | June | June |
By year
Seasonality
0Feb
1Mar
2Apr
1May
8Jun
10Jul
4Aug
3Sep
2Oct
0Nov
0Dec
0
Recorded events
All 31 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 |
|---|---|---|---|---|---|---|---|
| 1 Jul 2024 | Flood | — | — | — | — | — | County |
| 24 Jun 2024 | Flood | — | $200K | $17K | — | — | County |
| 12 Jun 2024 | Flash Flood | — | $25K | $15K | — | — | County |
| 12 May 2023 | Flash Flood | — | $500K | — | — | — | County |
| 14 Mar 2019 | Flood | — | — | — | — | — | County |
| 13 Mar 2019 | Flood | — | $2.2M | — | — | — | County |
| 20 Aug 2018 | Flash Flood | — | — | — | — | — | County |
| 18 Jun 2018 | Flood | — | — | — | — | — | County |
| 1 Sep 2014 | Flood | — | $5K | $10K | — | — | County |
| 1 Sep 2011 | Flood | — | $5K | — | — | — | County |
| 1 Aug 2011 | Flood | — | $7.0M | — | — | — | County |
| 1 Jul 2011 | Flood | — | $10K | — | — | — | County |
| 1 Jun 2011 | Flood | — | $150K | — | — | — | County |
| 26 May 2011 | Flood | — | $5K | — | — | — | County |
| 1 Jun 2010 | Flash Flood | — | $5K | — | — | — | County |
| 8 Jun 2008 | Flood | — | — | — | — | — | County |
| 30 May 2008 | Flood | — | — | — | — | — | County |
| 6 May 2007 | Flood | — | — | — | — | — | County |
| 6 May 2007 | Flood | — | — | — | — | — | County |
| 5 May 2007 | Flash Flood | — | $15M | — | — | — | County |
| 22 May 2004 | Flash Flood | — | — | — | — | — | County |
| 7 Aug 1999 | Flash Flood | — | $100K | — | — | — | County |
| 19 Jul 1999 | Flash Flood | — | — | — | — | — | County |
| 27 Jun 1999 | Flash Flood | — | — | — | — | — | County |
| 1 May 1997 | Flood | — | — | — | — | — | Forecast zone |
| 2 Apr 1997 | Flood | — | — | — | — | — | Forecast zone |
| 18 Feb 1997 | Flood | — | — | — | — | — | Forecast zone |
| 16 Jul 1996 | Flood | — | $1.5M | $8.0M | — | — | Forecast zone |
| 21 Jun 1996 | Flood | — | $7.5M | $24M | — | — | Forecast zone |
| 21 Jun 1996 | Flash Flood | — | — | — | — | — | County |
| 21 Jun 1996 | Flash Flood | — | — | — | — | — | County |
Questions and answers
How many flood events has Harrison County had?
31 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 Harrison County?
1 Jul 2024 (Flood). Records reach NCEI about 120 days after the month ends.
What was the most damaging flood event recorded in Harrison County?
The flood of 21 Jun 1996, with property damage estimated by NCEI at $7.5M and crop damage at $24M.
How does Harrison County compare with Iowa for flood?
4.4 events per 100 square miles against 13.2 statewide; the county holds 31 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.