I've noticed the same general idea. You can usually get some hints about the winter from aspects of the warm season pattern. I'm feeling pretty optimistic we will get several at bats this winter with near to above normal snow for many.

We had a big -SLP 60-90N this Summer. For whatever reason, since 2012 it has had an almost perfect correlation with follow Winter -AO. late August also broke the record for lowest 500mb on record for the month in the N. Hemisphere. When you see that stuff in the warm season, it is usually indicating more -ao/-epo potential for the cold season.

Actually the 50 hPa ECMWF has a full split with 3 daughter vortices. It's ideal to have one of these overhead as often troughs tend to want to focus beneath these. The way I read this is a tendency for cold into the US as we get deeper into December.

I hope whatever we have lasts until Christmas

Very long duration SSW on the weeklies that came out today. Stratosphere looks to remain weak through December.