Death Valley National Park in September

November through March is prime time. Daytime temperatures sit in the comfortable 60-75°F range, and nights drop to the 40s. January and February bring occasional wildflower blooms if winter rains cooperate. April and October are shoulder seasons — still manageable but getting warm. Expect highs in the 80s and 90s. Early mornings and late afternoons work best for hiking. May through September? Only for the truly prepared. Summer temperatures routinely exceed 115°F, and the pavement can literally melt your shoes. If you must visit in summer, start activities before sunrise and retreat to air conditioning by 10 AM. Winter nights can surprise you. Temperatures drop below freezing at higher elevations, and snow occasionally dusts the peaks. Pack accordingly.