Potter County

Population 2,377 (2025) 861 sq mi

Potter County has recorded 20 tornadoes since 1950, 54th most of 66 counties in South Dakota; the most recent was on July 26, 2011.

Hazard fingerprint for Potter County Tornado: 31th percentile. Tropical: 0th percentile. Wildfire: 0th percentile. Flood: 16th percentile. Hail & wind: 33th percentile. Heat: 56th percentile. Cold: 87th percentile. Winter: 65th 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 195020

At a glance

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

Tornadoes since 1950

20

54th of 66 in South Dakota

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

Details

Strongest tornado

F2

June 18, 1964, 24.6 mile path

Federal disaster declarations

16

Most recent: Flooding, 2023

Details

Record high

116°F

July 15, 2006

Details

Record low

−40°F

January 1, 2018

Details

Snowiest season

84.7in

Winter of 2010-11

Costliest event since 1996

$150K

Flood, April 10, 2023

Details

Tornadoes

About one every 3.8 years since 1950, none rated F3/EF3 or stronger.

Strongest

June 18, 1964

F2, 24.6 mile path

200 yards wide.

Most recent

Tuesday, July 26, 2011

EF0, 0.1 mile path

15 years ago.

Tornadoes by decade Doppler radar era² 1950s: 3 3 1960s: 6 6 1970s: 3 3 1980s: 2 2 1990s: 1 1 2000s: 4 4 2010s: 1 1 2020s: 0 1950s1960s1970s1980s1990s2000s2010s2020s
Recorded tornadoes per decade. The 2020s are incomplete.
Tornadoes by month J: 0 F: 0 M: 0 A: 3 M: 3 J: 9 9 J: 3 A: 2 S: 0 O: 0 N: 0 D: 0 JFMAMJJASOND
By month of occurrence, all years.

Every recorded tornado

Tornadoes in Potter County since 1950
Jul 26, 2011EF00.11000
Jun 16, 2009EF00.52500
Jun 16, 2009EF00.21000
Jun 24, 2006F01.01000
Jun 11, 2003F00.12500
May 21, 1995F00.11000
Aug 3, 1981F10.11000
Aug 3, 1981F10.11000
Jun 19, 1979F10.11000
Jun 6, 1971F00.11000
Jul 18, 1970F20.11000
Jun 22, 1966F10.11000
Jun 22, 1966F10.11000
Jul 22, 1965F10.11000
May 8, 1965F00.11000
May 8, 1965F00.11000
Jun 18, 1964F224.620020
Apr 19, 1955F218.22700
Apr 19, 1955F22.310000
Apr 19, 1955F210.86700
  1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Potter 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

No large wildfire has been mapped here since satellite mapping began in 1984.

Smoke overhead

Smokiest year

2021: 61 days

Heavy smoke on 39 days in 2021, the most of any year.

Last 10 years

31.9 days a year

Medium or heavy smoke, 2016 to 2025.

2025

27 days

Medium or heavy smoke. 38 so far in 2026.

Days with medium or heavy smoke overhead, by year 2011: 7 2012: 29 2013: 14 2014: 13 2015: 25 2016: 11 2017: 20 2018: 35 2019: 9 2020: 24 2021: 61 61 2022: 23 2023: 59 2024: 50 2025: 27 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

No federal flood insurance claims are recorded for this county.

Flood events since 1996

  • Flood10
  • Flash Flood9

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

Drought

In severe drought or worse for 147 of 1,581 months since 1895 (9%); the longest spell lasted 33 months.

147

Months in severe drought or worse since 1895

60

Months in extreme drought

9%

Share of all months, severe or worse

36

Drought reports to the Weather Service since 1996

Lowest reading

August 1934

−8.35, extreme drought

Longest severe spell

33 months

May 1936 to January 1939.

Latest month

September 2026

+1.37, slightly wet

Last severe month: July 2021.

Months in severe drought or worse, by year 1895: 0 1896: 0 1897: 0 1898: 1 1899: 0 1900: 0 1901: 4 1902: 0 1903: 0 1904: 0 1905: 0 1906: 0 1907: 0 1908: 0 1909: 0 1910: 0 1911: 2 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: 5 1927: 0 1928: 0 1929: 0 1930: 0 1931: 4 1932: 0 1933: 6 1934: 12 12 1935: 12 1936: 10 1937: 12 1938: 12 1939: 11 1940: 11 1941: 6 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: 7 1956: 5 1957: 0 1958: 0 1959: 2 1960: 0 1961: 0 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: 6 1977: 0 1978: 0 1979: 0 1980: 5 1981: 0 1982: 0 1983: 0 1984: 0 1985: 0 1986: 0 1987: 0 1988: 5 1989: 0 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: 1 2003: 0 2004: 0 2005: 0 2006: 3 2007: 0 2008: 0 2009: 0 2010: 0 2011: 0 2012: 3 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

2 earthquakes of magnitude 4 or more within 50 miles since 1900; the largest was magnitude 4.4 in 1983.

0

Magnitude 2.5+ inside the county since 1973

6

Magnitude 3+ within 50 miles since 1973

2

Magnitude 4+ within 50 miles since 1900

0

Magnitude 5+ within 50 miles since 1900

Largest within 50 miles

March 4, 1983

Magnitude 4.4

16 km N of Fort Thompson, South Dakota; 47.9 miles away, 3.1 miles deep.

Most recent, magnitude 3 or more

May 30, 2024

Magnitude 3.7

38 km NNW of Pierre, South Dakota; 16.3 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: 1 1 1984: 0 1985: 0 1986: 0 1987: 0 1988: 0 1989: 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: 1 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: 1 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
Mar 4, 19834.447.93.116 km N of Fort Thompson, South Dakota
Dec 31, 19614.247.414.330 km WSW of Fort Pierre, South 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

562 events in the National Weather Service record, 480 of them since 1996.

78

Hail reports, 1 inch or larger

10

Hail, 2 inches or larger

126

Damaging gusts, 58 mph+

93

Winter weather events since 1996

11

Heat events since 1996

39

Cold events since 1996

Largest hail

August 28, 2011

3.00 inches

Strongest measured or estimated gust

June 21, 1956

100 mph

More event types since 1996

Other Storm Events types since 1996
Lightning100Jun 17, 2001
Dense fog and smoke100May 17, 2023

Costliest events since 1996

  1. Apr 10, 2023Flood$150,000
    National Weather Service narrative

    The snowfall during the season in northeast and central South Dakota exceeded normal levels, with many locations ranking among the top 10 for the snowiest seasons. Additionally, the late spring conditions were unusually cold, resulting in a persistent and exceptionally deep snowpack until early April. The depth of the snowpack ranged from 15 to 30 plus inches, containing approximately 4 to 8 inches of snow water equivalent. However, the weather pattern shifted to abnormally warm conditions in the middle of April. Starting from April 9th, temperatures rapidly rose into the 40s and 50s in areas with deep snowpack, and occasionally reached the 60s and 70s thereafter. The rapid…

  2. Apr 1, 2019Flood$110,000
    National Weather Service narrative

    The continuation of snowmelt from a much above normal snowfall winter combined with a historic heavy snow/blizzard in mid-April resulted in widespread flooding across central and northeast South Dakota. Countless roads along with thousands of acres of cropland were flooded throughout April. Impacts include damaged roads, culverts, and bridges, and livestock, homes, and businesses were affected. Delayed planting resulted across all of the region as well. Cattle and calves were stressed by the cold and wet pattern, as the mud and cold caused some sickness with the livestock. Flooded roads made it difficult for many farmers or ranchers to get to their fields or livestock. There was a…

  3. Sep 2, 1999Flash Flood$14,000
    National Weather Service narrative

    Very heavy rains from thunderstorms repeatedly going over the same area resulted in extensive flash flooding in a 30 to 40 mile wide band from Fort Pierre in southeast Stanley County to Hecla in northeast Brown County. Rainfall amounts in this corridor ranged from 3 to 7 inches. As a result, the communities of Blunt in Hughes County and Onida in Sully county were severely flooded. Most of the homes and businesses were flooded throughout Blunt and Onida causing severe damage. Only a few homes in these communities were spared from receiving water in there basements. Most homes also experienced sewer backup. The sewer systems in both Onida and Blunt were flooded and shutdown. Many…

  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 Onida 4 Nw, 25.2 miles from the county’s population centre, with records from 1921.

All-time high
116°FJul 15, 2006
All-time low
−40°FJan 1, 2018
Warmest night
83°F2 times, most recently Jul 3, 1949
Coldest day
−18°F2 times, most recently Jan 14, 1972
Wettest day
6.21 inAug 2, 1953
Snowiest day
17.0 inApr 11, 2019
Hottest year
2021mean 51.0°F
Coldest year
1996mean 41.1°F
Wettest year
200729.01 in
Driest year
19769.88 in
Snowiest season
84.7 in2010-11
Average monthly high and low temperature and precipitation, last 30 years, Onida 4 Nw 32°F 27° 7° 0.5 Jan 32° 10° 0.7 Feb 45° 21° 0.9 Mar 58° 32° 1.9 Apr 69° 44° 3.0 May 80° 55° 3.4 Jun 88° 61° 2.5 Jul 85° 58° 2.7 Aug 77° 50° 1.9 Sep 60° 36° 1.7 Oct 45° 22° 0.6 Nov 31° 11° 0.6 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 1976: 41 1977: 15 1978: 20 1979: 7 1980: 35 1981: 11 1982: 15 1983: 31 1984: 16 1985: 21 1986: 6 1987: 21 1988: 37 1989: 31 1990: 12 1991: 12 1992: 1 1993: 2 1994: 12 1996: 7 1997: 3 1998: 20 1999: 10 2000: 14 2001: 24 2002: 30 2003: 16 2004: 7 2005: 22 2006: 32 2007: 14 2008: 5 2009: 5 2010: 12 2011: 10 2012: 24 2013: 7 2014: 1 2015: 8 2016: 12 2017: 45 45 2018: 12 2019: 1 2020: 4 2021: 24 2022: 17 2023: 8 2024: 5 2025: 12 19761986199720072017
Days reaching 95°F each complete year, last 50 years. Thirty-year average: 13.7.
Snowfall by winter 1976: 47.0 in 1978: 35.8 in 1979: 23.8 in 1981: 52.8 in 1982: 14.0 in 1983: 28.0 in 1984: 37.6 in 1985: 62.0 in 1986: 56.6 in 1987: 16.0 in 1988: 56.5 in 1989: 38.3 in 1990: 53.4 in 1991: 31.9 in 1992: 54.3 in 1993: 58.6 in 1994: 72.6 in 1995: 53.4 in 1996: 76.3 in 1997: 41.8 in 1998: 34.7 in 1999: 26.6 in 2000: 70.6 in 2001: 33.5 in 2002: 32.5 in 2003: 50.4 in 2004: 17.9 in 2005: 50.1 in 2006: 42.4 in 2007: 32.4 in 2008: 43.8 in 2009: 49.6 in 2010: 84.7 in 84.7 2012: 59.8 in 2013: 50.7 in 2014: 29.3 in 2015: 40.0 in 2016: 44.6 in 2017: 48.1 in 2018: 75.5 in 2019: 50.4 in 2020: 34.1 in 2022: 29.7 in 2023: 2.0 in 2024: 2.9 in 2025: 16.6 in 19761988199820082019
Total snowfall each winter (July to June), last 50 winters.

Median first snow

November 10

Earliest: October 1, 1999

Median last snow

April 5

Latest: May 14, 1916

0 of 78 winters had no measurable snow.

Station Onida 4 Nw (USC00396292), 1,851 ft elevation, 25.2 miles from the population centre. Daily records from 1921 to October 17, 2026; 98.5% 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: Flooding, July 6, 2023.

Federal disaster declarations
Jul 6, 2023FloodFloodingMajor disasterDR-4718-SD
Feb 27, 2023Winter StormSevere Winter Storms and SnowstormMajor disasterDR-4689-SD
Apr 5, 2020BiologicalCovid-19 PandemicMajor disasterDR-4527-SD
Mar 13, 2020BiologicalCovid-19EmergencyEM-3475-SD
Jun 7, 2019FloodSevere Winter Storm, Snowstorm, and FloodingMajor disasterDR-4440-SD
May 13, 2011FloodFloodingMajor disasterDR-1984-SD
Mar 10, 2010Severe StormSevere Winter StormMajor disasterDR-1887-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
May 26, 1995FloodFloodingMajor disasterDR-1052-SD
Mar 14, 1995SnowstormSevere Winter StormsMajor disasterDR-1045-SD
Jun 21, 1994Severe StormSevere Storms and FloodingMajor disasterDR-1031-SD
May 3, 1986FloodSevere Storms & FloodingMajor disasterDR-764-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 Potter County stands among 66 counties in South Dakota and 3,143 in the United States.

Ranks
Tornadoes since 19502054 / 661,572 / 3,143
Tornadoes rated F3/EF3 or stronger0——
Tropical cyclones within 50 mi0——
Hurricane-strength passes within 50 mi0——
Wildfire acres since 19840——
Flood insurance claims0——
Flood insurance paid$0——
Disaster declarations1647 / 662,158 / 3,143
Flood events since 19961955 / 662,557 / 3,143
Hail and wind events since 199627157 / 661,403 / 3,143
Winter storm events since 19969361 / 661,053 / 3,143
Reported damage since 1996$274,00058 / 663,066 / 3,143
River crests at major flood stage0——
High tide flooding days a year, last 10 years0.0——
Months in severe drought since 189514729 / 661,018 / 3,143
Medium or heavy smoke days a year, last 10 years31.915 / 66129 / 3,143
Earthquakes M4+ within 50 mi since 1900223 / 661,151 / 3,143
Earthquakes M2.5+ in the county since 19730——

Neighbouring counties

Neighbouring counties
Dewey County28018,0310
Edmunds County3102,8906
Faulk County22003
Hyde County1501,2681
Sully County2202,7895
Walworth County3002,7780

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 USC00396292.
  • 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.