The climatic conditions prevalent in the Black Hills of South Dakota during September significantly impact the visitor experience at the Mount Rushmore National Memorial. Typically, this month offers a transition from summer to fall, characterized by gradually cooling temperatures and fewer crowds compared to the peak summer months. Daytime highs average in the 60sF (15-20C), while nighttime lows can dip into the 40sF (4-9C). Rainfall is generally light and less frequent than in the preceding summer months.
Understanding the typical weather patterns for this period allows visitors to pack appropriately and plan activities accordingly. Pleasant daytime temperatures are ideal for hiking the Presidential Trail or exploring other nearby attractions like Custer State Park. The cooler evenings are perfect for stargazing, as the Black Hills region offers minimal light pollution. Historically, September has provided a more comfortable viewing experience at the memorial due to the decreased crowds and favorable weather. This contributes to a more relaxed and enriching experience for visitors interested in history, geology, and the natural beauty of the area.