I'm beginning to think that when it comes our region, outside of strong ENSO events, ENSO has little correlation on us. We've seen weak events and moderate events which have produced poor snow winters, cold winters, warm winter, prolific snow winters, etc. I know there are stats and data out there on this I just don't know it off the top of my head, but let's say like 55% of weak La Nina winters produced above-average snowfall across the major climo sites...that's not really much of a correlation.
Given where our region is located, there are so many other influences which help shape and define the pattern that I think at the end of the day the overall correlation of ENSO to us is very little (outside of strong events).
I've gone back to the drawing board with assessing La Nina Events, EL Nino events, neutral phases. Starting from scratch with breaking down events by strength (using the oceanic definitions) for the ENS-ONI, ONI, RONI and then looking at SOI data (using Long Paddock method), and then will incorporate MEI data. When it comes to ENSO and defining events, there is so much focus and emphasis on just oceanic SST's but the atmospheric response may be just as critical or hold more weight than the state and structure of SST's.
I've also always wondered how much of an influence patterns over Europe/Asia get the ball rolling. How the pattern evolves here eventually has downstream ramifications across the PAC...and this is when you introduce influences such as ENSO/MJO activity which help shape the pattern across the PAC...then this eventually has downstream ramifications on the pattern across North America, however, you also have what's going on within the PNA/EPO/NAO/AO domains which will help shape the pattern across North America.
What sucks is we have ENSO data which dates back to the 1800's but obviously that data needs to be used with precaution and we don't have a great database on variables such as OLR, winds, SSTs really until the satellite era began.