San Francisco Weather in October

San Francisco's climate is shaped by its position on a peninsula surrounded by the Pacific Ocean and San Francisco Bay. The coastal fog (Karl the Fog) rolls in through the Golden Gate each summer afternoon, keeping temperatures mild year-round. The city has dramatically different microclimates — the Sunset District fog-bound while the Mission basks in sun on the same day.

Foliage season in temperate cities. Often the best month to visit Europe.