Answer:
Advection fog.
Explanation:
Advection fog is most common along our Orange County beaches as well as in San Francisco because it is due to horizontal movement of air and it occur when the warmer and more moist air flow through the colder ground surface which lead to the cooling of the near air surface of the beach to below it's dew points and thus can happen even when it us windy and cloudy. It is common in West coast of USA.
