Good question.
Actually, conditions in the Pacific Ocean where El Ninos and La Ninas occur are in a La Nina state. In fact, as we have progressed through autumn, the La Nina has steadily strengthened and is now a moderate one vs. a weak one back in early autumn.
With that said, the current jetstream positions across North America are actually an almost textbook El Nino setup. Why is this happening? That is the million dollar question and one in which the answer is not known. In fact, if we knew what was causing the pattern to do what it is doing, then longer term (seasonal) forecasts would be considerably more accurate.
There are signs that as we head into the Christmas holiday period, the pattern may become a little more winter-like across the north central US. Not barbarically cold, with massive snow storms, but a heck of a lot closer to what should be occurring than is occurring right now.
Let's hope that when things get more winter-like, they stay that way and not poop out like has happened twice so far this season.
-John
