South Dakota's Extreme Temperatures: Record High 117°F, Record Low -58°F

Highest Temperature Ever Recorded

117 °F (47.2 °C) — July 13, 2021, in Mobridge (north-central SD, near the Missouri River).

Lowest Temperature Ever Recorded

-58 °F (-50 °C) — February 17, 1936, in Spearfish (in the Black Hills region).

Context

South Dakota's continental climate—far from moderating oceans—produces extreme seasonal swings. Summer heat waves can push temperatures above 110°F, while Arctic air masses in winter routinely bring sub-zero readings, especially in the Black Hills and northern plains. The 1936 cold wave remains one of the most severe in U.S. history.