We went here over the holiday seasons, and it was appropriately cold, windy and foggy. The Northern California coast tends to be rocky, windy, and treacherous. Because it's in California, San Francisco is often associated with sunshine, surfing and palm trees, when in fact the weather is characterized by dense, low-lying fog and gusts of wind, and if it's sunny it is a brisk sunshine, not a pleasant, warm, lazy one.
But all this, combined with all its hills, contributes to San Francisco's airiness, which I guess isn't so refreshing when you want to go out at night during the summer and have to wear several jackets, but contributes to a light, crisp sort of feel, which east coast cities are definitely lacking. They always feel as if they are broiling under the pavement during the summer, but San Francisco seems to be perched atop a cool breezy hill. It never feels stuffy. Sometimes when I go back I think stuff like, "This is the air I was meant to breathe!" Plus we have no bugs.
Being in this environment, among native Northern California plants and trees (and non-native ones which we have adopted as our own, like eucalyptus) really takes me back to my childhood- I have many photos of me in preschool on nature walks on the coast, all of us huddled together in sweatshirts.