Mount Rushmore in August

May through October offers the best weather, but July brings crushing crowds and 90-degree heat. September hits the sweet spot — warm days, cool nights, and autumn colors starting to show in the Black Hills. The monument stays open year-round, but winter temperatures drop to 20 degrees and snow can make driving treacherous. Spring weather stays unpredictable through April, with possible snow storms. Summer means 6am sunrises hitting the monument faces perfectly, creating the best photo opportunities. But you'll share that moment with 3 million other annual visitors. The lighting ceremony happens nightly at 9pm in summer, 7pm in fall — worth staying for if you can handle the patriotic speeches.