December 4-9 Major Snow Event Discussion (Updated 11/30)

Bear in mind track is not set in stone and will likely shift before event occurs.

The models continue to shift northward, and because the GFS is moving towards the ECMWF solution, as are the ensembles, we have deemed it appropriate to make a rough sketch of a graphic. We are expecting a strong ridge of high pressure to hold in place on the East Coast and also keep much of the East warmer. This ridge will be pulling in warm, moist air from the Gulf of Mexico, creating an apt environment for some showers, depending on the moisture amount when the system comes through. To the west of the storm track, a cold blast of air may come down from portions of Canada in the wake of this storm. As this storm moves towards the north, a potential cold front extending from it will likely push away the warmer air and also help along the colder air. On the bottom side of the storm track, rain is widely expected thanks to the massive ridge in the East. This system will be grabbing the warm air and using it as moisture, which may help along the snowfall and rainfall totals in the end. For areas on the north side of this system, snow will occur. It is expected that the heaviest snowfall totals will occur right next to the track itself, where the moisture bands will be the tightest swirling around the low. This colder air that may also be in place would help the potential for snow as well.
The reason why this storm is not going south is because of the ridge and the cold air. It is a 'sandwich' situation, with two factors on the outside and the storm in the middle. The stronger component (ridge or cold air) will be the more determining factor for this storm. At this point, it appears that the ridge will be stronger and thus will push the storm farther west and north. If, for some reason, the models backtrack and decide that the ridge will be much weaker, then the storm track would likely short farther south. What is interesting about that is how the GEM model is following that potential of a stronger cold blast.
What may also be a factor is how fast the storm moves, and may play a bigger part than we may be noticing. The GEM has the storm track more south because that cold blast is coming out first instead of the storm as the storm moves slower and is thus pushed south. The ECMWF moves very fast, much faster than some other models. Thus, the storm comes first rather than the cold air. This would be a lose-lose situation, because less snow would fall and more rain would fall as the storm moves faster and is actually a bit north of the forecast graphic above.
We are consulting with other weather enthusiasts for their take on the storm track, so if you have anything to offer, drop a comment below- we'll respond to any questions you have.

Remember- this graphic is nowhere near set in stone, and was created to show current model guidance. The situation will change, and it looks like the situation should get itself intact going into the weekend.