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Flood in Stanley County, South Dakota

33 floods and flash floods events in the NCEI Storm Events record, 1950 to 2026. Event types counted: Flood, Flash Flood, Coastal Flood, Lakeshore Flood.

33 events · 0 deaths recorded · peak month June · county share of state 1.0%

2026-06-29: Flood2025-09-18: Flood2025-09-18: Flood2024-08-21: Flood2019-06-01: Flood2019-05-31: Flood2019-05-01: Flood2019-04-01: Flood2019-03-27: Flood2019-03-25: Flood2018-06-27: Flood2017-08-21: Flood2011-09-01: Flood2011-08-01: Flood2011-07-05: Flood2011-07-01: Flood2011-06-21: Flood2011-06-20: Flood2011-06-20: Flood2011-06-01: Flood2011-05-24: Flood2008-06-02: Flood2007-06-12: Flood
Flood event locations in and around Stanley County. Dots: Flood event locations in the kept record. Boundaries: US Census Bureau.

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.

NCEI records 33 flood events in Stanley County, South Dakota, between 1950 and 2026, spread over 14 years.

June is the busiest month, with 9 of the recorded events. The last 20 years account for 23 events against 10 in the 20 years before, a change that reflects reporting practice as much as weather.

The county holds 1% of the 3,390 flood events recorded in South Dakota; its 2.3 per 100 square miles compares with 4.5 statewide.

Compared with South Dakota

MeasureStanley CountySouth DakotaUS
Flood events since 1950333,390183,559
Per 100 square miles2.34.55.2
Per 10,000 residents108.837.95.5
Deaths recorded0102,961
Busiest monthJuneJuneJune

By year

195019882026
Flood events recorded in Stanley County per year, 1950 to 2026 (2026 is partial).

Seasonality

Jan
0
Feb
1
Mar
5
Apr
2
May
5
Jun
9
Jul
2
Aug
4
Sep
5
Oct
0
Nov
0
Dec
0
Flood events in Stanley County by month of occurrence, all years.

Recorded events

All 33 events, most recent first. Magnitude is hail size, tornado rating or wind speed as recorded.

DateEvent typeMagnitudeProperty damageCrop damageDeathsInjuriesGeography
29 Jun 2026Flood—————County
18 Sep 2025Flood—————County
18 Sep 2025Flood—————County
21 Aug 2024Flash Flood——$12K——County
1 Jun 2019Flood——$2.9M——County
31 May 2019Flood—————County
1 May 2019Flood—————County
1 Apr 2019Flood—————County
27 Mar 2019Flood—————County
25 Mar 2019Flood—————County
27 Jun 2018Flash Flood—————County
21 Aug 2017Flash Flood—————County
1 Sep 2011Flood—————County
1 Aug 2011Flood—————County
5 Jul 2011Flash Flood—————County
1 Jul 2011Flood—————County
21 Jun 2011Flood—————County
20 Jun 2011Flash Flood—————County
20 Jun 2011Flood—————County
1 Jun 2011Flood—————County
24 May 2011Flood—————County
2 Jun 2008Flash Flood—$30K———County
12 Jun 2007Flash Flood—————County
20 Aug 2006Flash Flood—————County
14 Mar 2001Flood—————Forecast zone
3 Sep 1999Flood—————Forecast zone
2 Sep 1999Flash Flood—$20K———County
1 May 1997Flood—————Forecast zone
1 Apr 1997Flood—————Forecast zone
21 Mar 1997Flood—————Forecast zone
21 Mar 1997Flood—————Forecast zone
20 Feb 1997Flood—————Forecast zone
27 May 1996Flood—————Forecast zone

Questions and answers

How many flood events has Stanley County had?

33 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 Stanley County?

29 Jun 2026 (Flood). Records reach NCEI about 120 days after the month ends.

What was the most damaging flood event recorded in Stanley County?

The flood of 1 Jun 2019, with property damage estimated by NCEI at $0 and crop damage at $2.9M.

How does Stanley County compare with South Dakota for flood?

2.3 events per 100 square miles against 4.5 statewide; the county holds 33 of the state's 3,390 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.