The Chilling Effect: Why San Francisco Gets So Foggy in the Summer

Includes video and interactives

To start, a beautiful time-lapse film by Simon Christen …

“The coldest winter I ever spent was a summer in San Francisco.”

Mark Twain may never have actually said it himself, but that doesn’t make the statement any less true. 

As any naive tourist shivering miserably in a tank top and Bermuda shorts might attest to, San Francisco in the summertime can be one chilly town. Even on days when temperatures in nearby cities climb into the 90s, it’s not uncommon to find much of San Francisco shrouded in a thick blanket of fog, the mercury barely reaching 60 degrees Fahrenheit.

If you’re still a bit foggy (sorry, couldn’t help myself) about why that is, scroll through this great interactive explainer created by Newsbound. Below that, a video by KQED’s Quest team digs deeper into the science of coastal fog.


  • Karl the Fog

    Great post about my cardiovascular system. I focus so much on my emotions, it’s good to hear how I actually work.

    • Cecilia Hinojosa-Einhorn

      The cutest post!