Pacifica has a warm-summer Mediterranean climate. Summer fogs often produce light drizzle at night and in the morning, and condensation from them drips from trees overnight. Park Pacifica, in the south-east, is known to be much sunnier than the rest of the city.
The same fog is why Cabrillo and Vizcaino sailed past the Golden Gate without seeing San Francisco Bay. No measurable snowfall has been recorded since records began.