After 2 days of relative consistency in weather models we are seeing some divergence today between the European model & the GFS model. The two models are fairly consistent with the next 5 days which really doesn't help matters since it is the 5 days that follow that are problematic in the forecast. Both models show a strong cold front approaching next Wednesday and then the models diverge. First things first however are the teleconnection indices that still show that there is potential for something to happen around the December 9-11 time frame.
The Pacific North America index remains very strongly positive right through the middle of December. The North Atlantic Oscillation rises from a strong negative reading this weekend to near neutral rather rapidly in the Dec 9-11 period. Often times systems tend to develop in the East when this happens. Yesterday the GFS was responding to this by showing a developing second wave on a cold front late next week.
Yesterday's GFS model run was perhaps a bit fast with this idea but since then it has been showing a much flatter low much further offshore with no real consequence. The GFS simply overwhelms the East with cold air which would leave no room for anything to happen. The upper flow shows a broad jet stream far to the south with re-enforcing surges of cold air coming down out of Canada...READ MORE AT http://www.meteorologistjoecioffi.com/index.php/2017/12/01/weather-models-winter-pattern-developing-has-forecast-challenges/