Weather
Photo: John A. Martini
The climate on Alcatraz is unpredictable and can change suddenly. Cold, foggy mornings may give way to sunny afternoons, which in turn can shift quickly back to more fog and blustery winds.
The most pleasant weather usually occurs during April, May and June, and then again during September and October. Summer brings some of the coolest weather and heaviest fog to the island, which surprises many out-of-town visitors to San Francisco.
Temperatures on Alcatraz seldom rise above 75°F (24°C) or fall below 38°F (3°C). It almost never snows on the island, but winters are wet and always cold. Afternoon winds are common during every season.
Rain occurs frequently during winter and early spring. Much of the Alcatraz tour route is along outside roadways without shelter from the rain, so dress for possible wet weather. (Rain gear is available for purchase at Hornblower Alcatraz Landing and in the island’s bookstores.)
Native San Franciscans have a saying: "Always dress in layers and hope to be pleasantly surprised."
