The above image shows changes in sea surface temperatures (SST's) from September 2012 to October 2012. The blues signify a cooling temperature trend, while reds display warming of the waters. If we take a look at the north central Pacific in whole, we see a stark cooling trend coming around from east Asian waters to the waters south of the Aleutian Islands. Also, notice a slight warming trend focused in and to the north of the Aleutian Islands to the west coast of Canada, as far south as Baja California. This warming then moves west, forming a backwards 'C' around the cold pool.
Because the PDO is so complicated, I'll put the effects as simple as possible. A positive PDO tends to bring cooler than normal temperatures to much of the nation, while a negative PDO brings warmer than normal temperatures to the Lower 48. So, if we do have this PDO switch from its current negative phase to a positive phase, we could see a cooler winter than I had accounted for.
Exciting times ahead!