A strong east asian mountain torque event is occurring right now, acting as a trigger. This is the strongest EAMT event we have seen since early september. EP heat flux anomalies have already been strengthening from 1 to 50hpa.
A classic wave 1 response has been occurring already with warming focusing around the bering sea/north pacific area as well as northern europe. By hour 96 we see a major uptick in heat flux with warmth propagating down towards 100hpa. What this means it that we can expect a weakened vortex in late october, extending perhaps into the first week of november. This supports the cold pattern showing up on the modelling in the long range.
What is concerning is the response that should occur afterwords in mid to late november, causing the vortex to strengthen even more then before. The LR models such as the euro and JMA have a warmer then normal month for the east which seems plausible given the pattern. To see the stratosphere already responding to wave breaking events is definitely positive for those wanting a SSW event later this winter. Downwelling +QBO/la nada analog years support more of a late january into feb event... should be interesting to track.