If you are on the far North Coast that time of year, keeping warm will be a bigger issue. The cold Pacific ocean keeps the surrounding coastline cool and foggy a lot in the summertime. Mark Twain worked some for the San Francisco Examiner newspaper and is quoted as saying: "The coldest winter I ever spent, was a summer in San Francisco." As a kid, I used to sit in above 90 degree evenings in Southern California (Hemet) watching the Dodgers play the Giants at Candlestick, and wondering why all the crowd was bundled up in heavy coats and watch caps there.