Severe Weather History


Hazard archive · 1950 — present

Flash Flood in Sioux County, Iowa

41

Recorded events

0

Direct deaths

0

Direct injuries

$1.7M

Property damage

Flash Flood in Sioux County, Iowa: 41 recorded events between 1999 and 2025. The strongest on record measured 0. That places the county #797 nationally and #11 statewide for this hazard.

Decade by decade

Flash Flood in Sioux County, Iowa: events per decade

Flash Flood in Sioux County, Iowa: recorded events per decade
Flash Flood in Sioux County, Iowa: recorded events per decade

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for flash flood in Sioux County is the 2010s, when 18 of the county's 41 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.

Within the Sioux County archive, flash flood makes up 5.9% of all recorded severe weather across 8 hazard types. Nationally the county sits at #797 for this hazard and #11 within Iowa, putting it in the 73.6 percentile of all U.S. counties.

Seasonality

Events by month

0Jan
0Feb
0Mar
2Apr
3May
15Jun
10Jul
8Aug
2Sep
1Oct
0Nov
0Dec

Jun is the peak month for flash flood in Sioux County with 15 recorded events, while Jan is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.

Most recent

Latest recorded events

DateLocationMagnitudeDamage
Jul 30, 2025MAURICE0$0
Jul 30, 2025ALTON0$0
Jul 30, 2025CARNES0$0
Jun 2, 2025HULL0$0
Jun 22, 2024HULL0$0
Jun 22, 2024SIOUX CENTER0$0
Jun 21, 2024MATLOCK0$0
Jun 21, 2024HULL0$0
Aug 5, 2023BOYDEN0$0
Aug 5, 2023BOYDEN0$0
Source: NOAA/NCEI Storm Events · dates UTC · recent entries may be preliminary

Other hazards here

More from Sioux County

County overview →

From the record

What the reports say

Written by National Weather Service staff at the time of the event · public domain

Quick answers

Frequently asked

How many flash flood events are on record in Sioux County, Iowa?

41 flash flood events are recorded in Sioux County between 1999 and 2025, causing 0 direct deaths.

What is the strongest flash flood recorded in Sioux County?

The strongest flash flood on record in Sioux County measured 0.

Where does the flash flood data for Sioux County come from?

All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.

Cite this page

“Flash Flood in Sioux County, Iowa.” Severe Weather History. severeweatherhistory.com/county/iowa/sioux-county/flash-flood/ · Data: NOAA/NCEI, FEMA, U.S. Census — public domain.


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