Why Summers in San Francisco Are So Cold and Foggy

Through June, July, and August, San Francisco has cooler temperatures than any other major U.S. city. And just inland, summer daily high temperatures in the 90s F (above 32°C) are the norm. What factors create such bizarre weather in San Francisco?

Video sources: Daniel Davis (self)

Image sources:
earth.nullschool.net
Google Earth
NASA Earth Observatory
NASA Goddard Space Flight Center

Wikipedia Creative Commons: King of Hearts, Jitze Couperus, Golden Frog, runner310.

Flickr Creative Commons: Ken Lund, NASA Goddard Space Flight Center.

Information Sources:

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Gilliam, Harold (July–September 2002). "Cutting Through the Fog: Demystifying the Summer Spectacle". Bay Nature.

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