Given its location at the base of the Black Hills and its proximity to the High Plains, the climate in Spearfish is highly variable at any time of the year.
Extreme winter maxima in the district are remarkably warm for its latitude and on January 19, 1921 Spearfish reached a remarkable , not only the hottest January temperature in South Dakota on record,[REF] but almost certainly the hottest temperature recorded in or near mid-winter anywhere so far from the equator.