The only thing I disagree with here is the negative NAO. Our big -NAO years like 09-10 and 10-11 were near the solar minimum. We are descending, but solar activity is still a lot higher than it was during those years. I would lean towards more of a neutral to slightly positive NAO. The more important factor is the fall pattern, we have diverged from the bone dry fall pattern that continued into the winter. We saw a mid fall shift from an extended dry stretch (leading to drought conditions), and it has shifted to a stormy pattern with frequent coastals.
This combined with the other factors mentioned has me very optimistic about this upcoming winter for New England, even if the negative NAO idea doesn’t pan out. When I think of a big snow pattern the first thing I think of is NOT a Greenland block, it’s a tall ridge over Montana.