Rapid City Weather in September

Rapid City at the base of the Black Hills has one of the most variable climates in the US. The city experienced 91 deaths from a 1972 flash flood when Canyon Lake Dam failed. Chinook winds can raise temperatures 50°F in hours, while blizzards can be extreme. The Black Hills to the west create strong orographic weather patterns.

Excellent shoulder season — warm with fewer tourists in many destinations.