San Pedro de Atacama in September

April through October brings the best weather – daytime temperatures hover around 20°C while nights drop to near freezing. The dry season means clear skies perfect for stargazing and photography. Summer (December-February) gets uncomfortably hot during the day, reaching 30°C+, but offers warmer nights for camping under the stars. Winter nights can hit -10°C, so pack serious cold-weather gear if you're visiting June through August. The rainy season barely exists here – San Pedro receives less than 15mm of precipitation annually. But when it does rain (usually January-March), flash floods can make some roads impassable. Book accommodations well ahead for July and August, when Chilean winter holidays bring domestic crowds.