Corson County

Population 3,781 (2025) 2,470 sq mi

Large wildfires have burned 57,819 acres of Corson County since 1984, 9th most of 66 counties in South Dakota; the largest was the Unnamed Fire in 1991.

Hazard fingerprint for Corson County Tornado: 16th percentile. Tropical: 0th percentile. Wildfire: 59th percentile. Flood: 17th percentile. Hail & wind: 24th percentile. Heat: 56th percentile. Cold: 86th percentile. Winter: 64th percentile. TORTROPFIREFLOODSEVEREHEATCOLDWINTER

Hazard fingerprint Each spoke is this county’s percentile among U.S. counties where that hazard occurs. How it is computed

2026
  • Tornado damage paths since 195023
  • Wildfire burn scars since 198415

At a glance

The record for Corson County in eight numbers. Each links to its section below.

Acres burned since 1984

57,819

9th of 66 in South Dakota

15 large fires; the largest was Unnamed, 1991

Details

Flood insurance claims

1

47th of 66 in South Dakota

$450 paid since 1978

Details

Tornadoes since 1950

23

43rd of 66 in South Dakota

Fewer than the typical South Dakota county, which has had 29

Details

Strongest tornado

F2

May 29, 1953, 0.5 mile path

Federal disaster declarations

16

Most recent: Covid-19 Pandemic, 2020

Details

Record high

112°F

July 16, 2006

Details

Record low

−37°F

Reached 2 times, most recently February 11, 1988

Details

Snowiest season

81.0in

Winter of 2022-23

Tornadoes

About one every 3.3 years since 1950, none rated F3/EF3 or stronger.

Strongest

May 29, 1953

F2, 0.5 mile path

33 yards wide.

Most recent

Sunday, September 14, 2025

EFU, 0.0 mile path

Within the past year.

Tornadoes by decade Doppler radar era² 1950s: 3 3 1960s: 2 2 1970s: 6 6 1980s: 3 3 1990s: 3 3 2000s: 2 2 2010s: 2 2 2020s: 2 2 1950s1960s1970s1980s1990s2000s2010s2020s
Recorded tornadoes per decade. The 2020s are incomplete.
Tornadoes by month J: 0 F: 0 M: 0 A: 2 M: 3 J: 9 9 J: 3 A: 5 S: 1 O: 0 N: 0 D: 0 JFMAMJJASOND
By month of occurrence, all years.

Every recorded tornado

Tornadoes in Corson County since 1950
Sep 14, 2025EFU0.0100
Jun 8, 2021EF00.21000
Aug 14, 2011EF00.21000
Aug 14, 2011EF00.21000
Aug 10, 2007EF00.21000
Aug 10, 2007EF00.32000
Jun 8, 1999F02.02000
Aug 17, 1995F00.11000
Jun 11, 1990F00.32000
Jun 27, 1984F00.11000
Jun 27, 1984F00.11000
Jun 21, 1983F00.11000
Jul 11, 1979F00.11000
Jul 11, 1979F00.11000
Jun 10, 1977F00.51000
May 18, 1977F00.11000
Jun 7, 1971F00.11000
Jun 7, 1971F00.11000
Jul 24, 1966F00.11000
May 8, 1965F00.11000
Apr 19, 1955F03.85000
Apr 19, 1955F07.25020
May 29, 1953F20.53320
  1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Corson County: 0.
  2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Hurricanes and tropical storms

No tropical storm or hurricane has tracked within 100 miles since records began in 1851.

Wildfire and smoke

57,819 acres burned in 15 large fires since 1984, equal to 3.7% of the land.

Largest

October 1, 1991

Unnamed Fire, 14,493 acres

14,494 acres inside Corson County.

Most recent

October 2, 2024

Stateline Fire

2,118 acres in total.

Acres burned since 1984, cumulative 1987: 1,8691991: 15,9321992: 1,1431999: 5,6042000: 11,8422006: 15,8982012: 3,9342024: 1,596 57,819 acres 198519901995200020052010201520202025
Running total of acres burned inside the county (line) and each year’s acres (bars).

Every large fire

Large wildfires since 1984
Stateline20241,5962,118
Cornstalk20121,4352,560
Mcintosh20121,1472,652
Crow Flats20121,3511,351
B Ward 120063,3253,326
Klein20061,0031,006
Stone Man Church200610,38910,389
Isabel20061,1801,179
Trible20009,7189,714
Ftmanuel20002,1242,121
Bullhead19995,6045,599
Unnamed19921,1431,143
Unnamed199114,49414,493
Unnamed19911,4371,436
Unnamed19871,8681,871
  1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

Smokiest year

2023: 60 days

Heavy smoke on 42 days in 2021, the most of any year.

Last 10 years

32.6 days a year

Medium or heavy smoke, 2016 to 2025.

2025

26 days

Medium or heavy smoke. 39 so far in 2026.

Days with medium or heavy smoke overhead, by year 2011: 4 2012: 22 2013: 13 2014: 12 2015: 24 2016: 13 2017: 21 2018: 35 2019: 11 2020: 24 2021: 60 60 2022: 23 2023: 60 2024: 53 2025: 26 201120122013201420152016201720182019202020212022202320242025
Days each year on which a satellite-traced plume of medium or heavy smoke covered the county’s population centre, 2011 to 2025.
  1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Floods and flood insurance

1 federal flood insurance claims since 1978, with $450 paid.

Federal flood insurance claims by year
Claims per year since 1978. Years with fewer than five claims are not shown.

Flood events since 1996

  • Flood41
  • Flash Flood14

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

Most severe crest

March 27, 1997

Oak Creek near Wakpala, 19.83 ft

9.83 feet above the 10.0 ft flood stage; major flooding by today’s categories.

Most recent moderate or major crest

April 12, 2023

Oak Creek near Wakpala, 14.01 ft

Moderate flooding.

Highest river crests above flood stage
Mar 27, 1997Oak Creek near Wakpala19.83+9.83Major
Mar 23, 2009Oak Creek near Wakpala19.52+9.52Major
Mar 14, 1995Oak Creek near Wakpala18.62+8.62Major
Mar 23, 1987Oak Creek near Wakpala18.35+8.35Major
Apr 4, 1986Oak Creek near Wakpala17.73+7.73Major
Jul 2, 2015Oak Creek near Wakpala17.46+7.46Major
Mar 31, 2019Oak Creek near Wakpala16.95+6.95Major
Mar 17, 2011Grand River (SD) near Little Eagle21.27+6.27Major
Mar 12, 1972Grand River (SD) near Little Eagle21.01+6.01Major
Aug 25, 2014Grand River (SD) near Little Eagle20.76+5.76Moderate
Jul 17, 2001Oak Creek near Wakpala15.33+5.33Moderate
Jun 18, 2014Oak Creek near Wakpala14.95+4.95Moderate
Mar 26, 1989Oak Creek near Wakpala14.89+4.89Moderate
Jun 14, 2007Oak Creek near Wakpala14.37+4.37Moderate
Mar 20, 2011Oak Creek near Wakpala14.35+4.35Moderate
Mar 23, 1987Grand River (SD) near Little Eagle19.16+4.16Moderate
Mar 23, 2010Oak Creek near Wakpala14.04+4.04Moderate
Apr 12, 2023Oak Creek near Wakpala14.01+4.01Moderate
Mar 12, 1996Oak Creek near Wakpala13.69+3.69Moderate
Mar 23, 1978Grand River (SD) near Little Eagle18.41+3.41Moderate
Jun 10, 2021Grand River (SD) near Little Eagle17.94+2.94Moderate
Mar 12, 1996Grand River (SD) near Little Eagle17.25+2.25Moderate
May 11, 1999Oak Creek near Wakpala12.48+2.48Minor
May 27, 2013Oak Creek near Wakpala12.19+2.19Minor
Mar 27, 1997Grand River (SD) near Little Eagle16.96+1.96Minor

River gauges

River gauges and their highest listed crests
Grand River (SD) near Little Eagle15.021.27 ftMar 17, 20112
Oak Creek near Wakpala10.019.83 ftMar 27, 19977
  1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

Drought

In severe drought or worse for 181 of 1,581 months since 1895 (11%); the longest spell lasted 24 months.

181

Months in severe drought or worse since 1895

72

Months in extreme drought

11%

Share of all months, severe or worse

55

Drought reports to the Weather Service since 1996

Lowest reading

August 1934

−8.44, extreme drought

Longest severe spell

24 months

July 1933 to June 1935.

Latest month

September 2026

+2.06, moderately wet

Last severe month: September 2021.

Months in severe drought or worse, by year 1895: 0 1896: 0 1897: 0 1898: 0 1899: 0 1900: 2 1901: 2 1902: 0 1903: 0 1904: 0 1905: 0 1906: 0 1907: 0 1908: 0 1909: 0 1910: 2 1911: 7 1912: 0 1913: 0 1914: 0 1915: 0 1916: 0 1917: 0 1918: 0 1919: 0 1920: 0 1921: 0 1922: 0 1923: 0 1924: 0 1925: 0 1926: 1 1927: 0 1928: 0 1929: 0 1930: 0 1931: 0 1932: 0 1933: 6 1934: 12 12 1935: 11 1936: 8 1937: 12 1938: 9 1939: 12 1940: 2 1941: 0 1942: 0 1943: 0 1944: 0 1945: 0 1946: 0 1947: 0 1948: 0 1949: 0 1950: 0 1951: 0 1952: 0 1953: 0 1954: 0 1955: 2 1956: 1 1957: 0 1958: 0 1959: 1 1960: 5 1961: 6 1962: 0 1963: 0 1964: 0 1965: 0 1966: 0 1967: 0 1968: 0 1969: 0 1970: 0 1971: 0 1972: 0 1973: 0 1974: 0 1975: 0 1976: 0 1977: 2 1978: 0 1979: 0 1980: 8 1981: 6 1982: 0 1983: 0 1984: 0 1985: 0 1986: 0 1987: 0 1988: 8 1989: 4 1990: 9 1991: 10 1992: 4 1993: 0 1994: 0 1995: 0 1996: 0 1997: 0 1998: 0 1999: 0 2000: 0 2001: 0 2002: 7 2003: 10 2004: 5 2005: 0 2006: 3 2007: 0 2008: 0 2009: 0 2010: 0 2011: 0 2012: 2 2013: 0 2014: 0 2015: 0 2016: 0 2017: 0 2018: 0 2019: 0 2020: 0 2021: 2 2022: 0 2023: 0 2024: 0 2025: 0 18951905191519251935194519551965197519851995200520152025
Months each year with a Palmer index of −3 or lower, 1895 to 2025. Twelve means the whole year.
  1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

Earthquakes

1 earthquake of magnitude 4 or more within 50 miles since 1900; the largest was magnitude 4.4 in 1968.

0

Magnitude 2.5+ inside the county since 1973

3

Magnitude 3+ within 50 miles since 1973

1

Magnitude 4+ within 50 miles since 1900

0

Magnitude 5+ within 50 miles since 1900

Largest within 50 miles

July 8, 1968

Magnitude 4.4

Near Huff, North Dakota; 46.1 miles away, 16.8 miles deep.

Most recent, magnitude 3 or more

December 8, 2020

Magnitude 3.2

10 km NNW of Bowdle, South Dakota; 30.3 miles away.

Earthquakes of magnitude 3 or more within 50 miles, by year 1973: 0 1974: 0 1975: 0 1976: 0 1977: 0 1978: 0 1979: 0 1980: 0 1981: 0 1982: 0 1983: 0 1984: 0 1985: 0 1986: 0 1987: 0 1988: 0 1989: 1 1 1990: 0 1991: 0 1992: 0 1993: 0 1994: 0 1995: 0 1996: 0 1997: 0 1998: 0 1999: 0 2000: 0 2001: 0 2002: 0 2003: 0 2004: 0 2005: 0 2006: 0 2007: 0 2008: 0 2009: 0 2010: 0 2011: 0 2012: 0 2013: 0 2014: 0 2015: 0 2016: 0 2017: 1 2018: 0 2019: 0 2020: 1 2021: 0 2022: 0 2023: 0 2024: 0 2025: 0 19731978198319881993199820032008201320182023
Per year, 1973 to 2025.

Every earthquake of magnitude 4 or more within 50 miles

Earthquakes of magnitude 4 or more within 50 miles
Jul 8, 19684.446.116.8Near Huff, North Dakota
  1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
  2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Severe weather and other events

946 events in the National Weather Service record, 875 of them since 1996.

196

Hail reports, 1 inch or larger

22

Hail, 2 inches or larger

236

Damaging gusts, 58 mph+

90

Winter weather events since 1996

11

Heat events since 1996

37

Cold events since 1996

Largest hail

August 27, 1983

3.00 inches

Strongest measured or estimated gust

August 23, 2021

112 mph

More event types since 1996

Other Storm Events types since 1996
Lightning100Aug 26, 1998
Dense fog and smoke100May 17, 2023

Costliest events since 1996

  1. Oct 26, 1996Winter Storm, Corson$120,000
    National Weather Service narrative

    An intense area of low pressure brought heavy rains to western Corson county. As colder air moved in behind the low and winds gusted to 50 mph, the rain changed to snow and three to five inches of ice formed on power lines and poles. One-hundred fifteen poles were snapped leaving about 400 people without power in the Mcintosh, Wautaga, and Keldron areas. Some people were without power for up to two days. Mcintosh received 6 inches of snow.

  2. Mar 20, 2009Flood$50,000
    National Weather Service narrative

    Rapid snowmelt caused Oak Creek to flood at Wakpala. The creek went above flood stage on March 20th and rose to a major flood stage of 19.3 feet on March 23rd. This stage was just a half of a foot from the record stage in 1997. The city of Wakpala was evacuated with several homes on the east side being flooded. The Red Cross set up shelter in the Wakpala Community Center.

  1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

Weather records

From Mclaughlin 2SW, 4.6 miles from the county’s population centre, with records from 1919.

All-time high
112°FJul 16, 2006
All-time low
−37°F2 times, most recently Feb 11, 1988
Warmest night
76°F2 times, most recently Jul 20, 2011
Coldest day
−22°F2 times, most recently Dec 21, 1989
Wettest day
4.88 inAug 18, 2007
Snowiest day
20.0 inMar 19, 1982
Hottest year
2012mean 47.5°F
Coldest year
2019mean 39.8°F
Wettest year
201930.51 in
Driest year
20069.44 in
Snowiest season
81.0 in2022-23
Average monthly high and low temperature and precipitation, last 30 years, Mclaughlin 2SW 32°F 24° 5° 0.4 Jan 29° 7° 0.5 Feb 41° 18° 0.8 Mar 56° 29° 1.7 Apr 68° 42° 3.3 May 79° 53° 3.4 Jun 86° 58° 2.6 Jul 84° 55° 2.6 Aug 74° 46° 2.0 Sep 58° 32° 1.4 Oct 42° 19° 0.6 Nov 29° 9° 0.7 Dec Precipitation, inches
Average daily high and low by month, and average monthly precipitation, over the last 30 years.
Days reaching 95°F per year 1995: 5 1997: 2 1998: 7 1999: 8 2001: 14 2002: 19 2003: 17 2004: 3 2005: 14 2006: 28 28 2007: 11 2009: 2 2010: 11 2011: 3 2012: 14 2013: 8 2014: 2 2015: 8 2016: 10 2017: 11 2018: 7 2019: 3 2022: 14 2023: 4 2024: 4 2025: 6 199520072018
Days reaching 95°F each complete year, last 50 years. Thirty-year average: 9.2.
Snowfall by winter 1976: 29.7 in 1984: 31.8 in 1986: 30.6 in 1989: 13.1 in 1990: 24.5 in 1991: 6.5 in 1998: 3.0 in 1999: 1.5 in 2000: 8.0 in 2001: 0.0 in 2002: 5.0 in 2006: 8.0 in 2008: 36.0 in 2009: 39.9 in 2010: 70.4 in 2012: 40.5 in 2013: 29.0 in 2014: 31.2 in 2015: 15.3 in 2016: 61.0 in 2018: 66.5 in 2019: 52.0 in 2022: 81.0 in 81.0 2023: 32.5 in 2024: 18.6 in 197620022018
Total snowfall each winter (July to June), last 50 winters.

Median first snow

November 17

Earliest: October 10, 2019

Median last snow

March 30

Latest: May 11, 2015

2 of 34 winters had no measurable snow.

Station Mclaughlin 2SW (USC00395406), 2,053 ft elevation, 4.6 miles from the population centre. Daily records from 1919 to October 22, 2026; 92.4% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

Federal disaster declarations

16 since 1953. The most recent: Covid-19 Pandemic, April 5, 2020.

Federal disaster declarations
Apr 5, 2020BiologicalCovid-19 PandemicMajor disasterDR-4527-SD
Mar 13, 2020BiologicalCovid-19EmergencyEM-3475-SD
Jul 28, 2014FloodSevere Storms, Tornadoes, and FloodingMajor disasterDR-4186-SD
Nov 8, 2013Severe StormSevere Winter Storm, Snowstorm, and FloodingMajor disasterDR-4155-SD
Jun 28, 2013Severe StormSevere Storms, Tornado, and FloodingMajor disasterDR-4125-SD
May 13, 2010Severe StormSevere Winter StormMajor disasterDR-1914-SD
Mar 10, 2010Severe StormSevere Winter StormMajor disasterDR-1887-SD
Jun 16, 2009Severe StormSevere Storms and FloodingMajor disasterDR-1844-SD
Dec 12, 2008SnowstormSevere Winter Storm and Record and Near Record SnowMajor disasterDR-1811-SD
Sep 10, 2005Coastal StormHurricane Katrina EvacuationEmergencyEM-3234-SD
Jul 22, 2005Severe StormSevere StormMajor disasterDR-1596-SD
Apr 7, 1997FloodSevere Flooding, Sever Winter Storms,Heavy Rains High WindsMajor disasterDR-1173-SD
Jan 10, 1997Severe StormSevere Winter Storms and Blizzard ConditionsMajor disasterDR-1156-SD
Mar 14, 1995SnowstormSevere Winter StormsMajor disasterDR-1045-SD
Jul 19, 1993Severe StormSevere Storms, Tornadoes & FloodingMajor disasterDR-999-SD
Jun 17, 1976DroughtDroughtEmergencyEM-3015-SD

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

How this compares

Where Corson County stands among 66 counties in South Dakota and 3,143 in the United States.

Ranks
Tornadoes since 19502343 / 661,396 / 3,143
Tornadoes rated F3/EF3 or stronger0——
Tropical cyclones within 50 mi0——
Hurricane-strength passes within 50 mi0——
Wildfire acres since 198457,8199 / 66428 / 3,143
Flood insurance claims147 / 662,799 / 3,143
Flood insurance paid$45048 / 662,844 / 3,143
Disaster declarations1647 / 662,158 / 3,143
Flood events since 19965522 / 661,299 / 3,143
Hail and wind events since 199661013 / 66260 / 3,143
Winter storm events since 19969065 / 661,092 / 3,143
Reported damage since 1996$170,00062 / 663,088 / 3,143
River crests at major flood stage912 / 66561 / 3,143
High tide flooding days a year, last 10 years0.0——
Months in severe drought since 18951814 / 66439 / 3,143
Medium or heavy smoke days a year, last 10 years32.68 / 6696 / 3,143
Earthquakes M4+ within 50 mi since 1900138 / 661,397 / 3,143
Earthquakes M2.5+ in the county since 19730——

Neighbouring counties

Neighbouring counties
Adams County ND1402,9431
Campbell County1702,7551
Dewey County28018,0310
Emmons County ND4305,66482
Perkins County46058,2550
Sioux County ND17065,6612
Walworth County3002,7780
Ziebach County24060,0903

Sources and vintage

Every number on this page comes from these public records.

  • Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
  • Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
  • Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
  • Storm events NOAA NCEI Storm Events Database, through 2026.
  • Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
  • Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
  • Weather records NOAA NCEI Global Historical Climatology Network Daily, station USC00395406.
  • River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
  • Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
  • Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
  • Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.