The models, in general, are flip-flopping a lot with this time period (which happens to be right before Thanksgiving and the biggest travel day of the year...).
The 06Z runs of the GFS/FV3 are now available - and they are much more in-line (and closer to what the FV3/ECMWF had in the 00Z runs).
And, of course, the 12Z GFS came in - and it was massively different again! The 12Z ECMWF has "stayed the course" with the feature approaching the Great Lakes on the 21st being relatively similar. Apparently the atmosphere is very sensitive right now to things happening out in the Pacific.
Once again - kudo's to Corey for the dProg/dT button on the webpage which makes it really easy to watch how the differences evolve between the different runs. Will be interesting to see how this case continues to play out.
Tim