A recent CPC blog post said: "We recommend that you track the verification skill scores over time (not just for one forecast), as they give you a feel for whether you should trust them or not. Any individual forecast could hit the mark or be way off". Consequently, below are the CPC seasonal forecasts for winter for the past 20 years. It is left to the reader to assess how "skillful" these outlooks are.
For the full breakdown see http://ggweather.com/cpc/verify/cpc_winter.htm
Jan Null, CCM
Golden Gate Weather Services