How is it that your winters are warmer than your summers?
I'm not sure but it really does feel nice today!
FOGGGGG...which starts about May. The onshore flow from the Pacific brings cold, wet fog more days than not. We haven't had many weather fronts in the last couple of weeks (which is kind of unusual) and the same offshore flow that is causing the Santa Ana winds (and fires) in Orange County is giving us nearly perfect weather this week. It is not all that unusual for February give us these kinds of 73 degree days in the city - in between storms.
Don't visit San Francisco during the fog months (May-August) without bringing a decent jacket!
The sun comes out in the winter.