Depends what part of California you live in. I live in a valley that regularly has temperatures between 100 - 110 fahrenheit(sometimes higher during a bad heat wave) during summer. It's never below 95 unless we're having a cold spell. Before this year, we had 3 or 4 cool summers in a row, that was nice. This year has been worse since we're getting Arizona's monsoon weather for some reason and it's bringing in all this muggy air.
But then I could take a 20-30 minute drive over the mountains and suddenly emerge in 70-80 degree weather.