Potter County, South Dakota

What hazards hit Potter County most?

The most frequent records are hail reports: 134 since 1960. 63% of its hail reports since 1960 fell in July and August. The rank column places the county among South Dakota's counties by days with a record per 1,000 square miles of land over each hazard's complete period.

Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.

How many tornadoes has Potter County had?

NOAA records 20 tornadoes in Potter County from 1955 to 2011, the strongest rated F2, with 0 deaths and 0 injuries recorded in the county. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.

Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 20 tornadoes whose track touched Potter County since 1950 (NOAA's county records number 20, the same count); along their whole tracks they killed 0 people.

Map of the strongest tornado tracks in South Dakota.

Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.

When was the last damaging storm in Potter County?

The most recent record with damage, injuries or deaths is the April 10, 2023 flood ($291,000 in damage in 2025 dollars).

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 snowmelt that followed resulted in extensive overland flooding in the region between April 10th and 18th. Flooding resulted in severe damage to public infrastructure. …
National Weather Service event narrative, NOAA Storm Events Database (search the full record, event 1097418)

Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.

The deadliest and costliest records

Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.

Is it getting more frequent?

Records per decade for Potter County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).

Extreme cold in the 2010s: 18 records against 5 in the decade before, 18 of them forecast-zone records. Cells marked z rose mostly through zone records. The local National Weather Service office files these once per forecast zone, so a change in how it draws its zones or splits a storm into records moves this count as much as the weather does; read it beside the Potter County days with a record above.

Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).

What time of year?

63% of its hail reports since 1960 fell in July and August. The two busiest months are in violet.

Source: NOAA NCEI Storm Events Database, records by the month they began.

Federal disaster declarations for Potter County

FEMA's register lists 16 declarations that include Potter County: 13 major disasters, 3 emergencies and 0 fire management assistance declarations. Most were for flood (6) and severe storm (4).

Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.

FEMA's modeled risk for Potter County

FEMA's National Risk Index rates Potter County Very Low overall, with an expected annual loss of $5.4 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.

Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.

Counties that share a border with Potter County

1. Edmunds County 819
2. Dewey County 814
3. Walworth County 663
4. Faulk County 615
5. Hyde County 568
6. Potter County 559
7. Sully County 525

Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.

Next

• Tornadoes in South DakotaEvery South Dakota tornado since 1950 and the counties with the most per square mile
• Hail in South DakotaThe state's hail reports, by county, year and month
• The South Dakota recordEvery hazard in the state, its deadliest events and its federal declarations
• FEMA's risk rating for each hazard in Potter CountyThe hazard risk calculator: 18 hazards beside the county's record
• Download Potter County's FEMA declarations (CSV)16 rows: every declaration that named the county, for your own analysis