I think +PNA still works. I've seen many cold periods lately, when the PNA lines up right. The -NAO is ridging north, and even the -AO and -EPO to an extent, but the W->E flow pattern is still in effect. The global +13dm -PNA over the total last 25 years is a major anomaly, and no one should be making assessments about snow seasons being over because of that anomaly. As far as I know, it's cyclical.