It was the only year that really matched up in terms of other global indicators like the PDO and EPO. 1957, 1986, 1994, and 2004 all had fairly robust +PDO signals in conjunction with a negative -EPO pattern that I expect will continue for the summer. Other cold phase oncoming Nino's such as 1965 and 1972 for example, had solidly negative PDO's. Much different SSTA profile in the Pacific as well among other atmospheric factors.