While much of South Dakota is flat, grassy plains, the western side of the state differs in its vast range of low, ponderosa pine covered mountains that make up the Black Hills (remember, Rapid is at the base). These mountains create (1) A natural barrier to shelter the Rapid City region from the harshest of winter weather, (2) and a downward slope that captures warm Chinook winds known for quick and temperature changes that can warm up cold winter days.
