I'm looking at taking a holiday with my sister and my son in California during December/early January 2013/14. We wanted to do outdoors stuff, some cycling, hiking and beaches (moderate level). Is the weather suitable for these sort of activities at this time of the year? I'm coming from Australia, so I don't mind cooler weather, but my sister is escaping the UK winter. Would if be good to tour with a company - usually I organise my own trips. Any advice very welcome.