If there's an SF earthquake I don't see the point of evacuating afterwards. Evacuating /before/ would be great, except unlike hurricanes, they're not predictable. SF weather is not very severe even in the wintertime. I'd say people whose homes are still standing and not at risk of collapse should just stay put. Those whose homes or neighborhoods are crashed should either seek shelter or get by outside (it can get chilly at night but no one will freeze). Main thing they should do is put ample supplies of fresh water or desalination equipment (pacific ocean) in place.