After an extended break from active weather, New England is looking at a potential nor'easter brewing for early next week. The energy source for this system is currently working through the Gulf of Alaska. As expected at this stage, there are multiple scenarios on the table for our region.
Models can struggle to hone in on what a system will do while it remains over the Pacific Ocean, which is why forecasters don't like to try to go into details about a storm system until it enters the upper air pattern over land. When this happens, it starts to become more clear on exactly where a storm will go.
Exactly where a storm goes is always crucial in determining what kind of precipitation type falls across New England. There remains a large spread in potential tracks, with the CMC and ICON currently bringing the system inside the 40/70 benchmark. This would lead to a mainly rain or mixing event in southern New England with more snow into northern New England (and possibly the higher elevations of southern New England). The further north the storm tracks, the further north rain/mixing will get.
What the CMC is currently showing for Tuesday morning. As always at this stage, DON'T take these model images verbatim:
The GFS has trended much further south, but is currently the outlier. This would lead to very little precipitation in northern New England and lighter rain/snow showers to southern New England. Based on how things have played out so far this winter, it makes sense that this is the outlier. Currently, we believe this is the least likely scenario.
The Euro model is sort of acting as a middle ground between these two solutions, with the system passing near, or just inside the benchmark. This would bring more of New England snowfall, but in the overall setup, may still favor mixing across southern New England outside the Worcester Hills and Berkshires, who would see mostly snow.
What the Euro is currently showing for Tuesday morning:
Looking at how trends have played out for the most part this winter, storms have looked like they would pass more to the south of New England several days out before trending further north as the system gets closer. That's why we're currently leaning more toward the CMC/Euro over the GFS at this time.
As always, intensity will come into play as well. The low passing near New England's south coast (the southern stream energy) will likely interact with a trough crossing the Great Lakes (the northern stream energy). The amount of interaction (or phasing) between these two pieces will be key in how the storm amplifies and how heavy precipitation (snow or rain) may be.
CMC showing the system coming together and approaching New England early next week:
Another major factor will be the amount of cold air in place. Big time warmth is coming to New England this weekend, with highs coming close to daily records in southern New England for Saturday. This obviously doesn't bode well for a snowstorm, however, colder air will begin filtering into the region by early next week. The question may come down to how quickly the colder air can get into the region, particularly southern New England.
Another trend storms have followed this season has been for a rain/snow line to be all the way into central New England before collapsing southward during the storm, with much of southern New England seeing rain at the onset before switching to snow from north to south and higher elevations to lower elevations. This could be the case with this system, though only time will tell if that plays out or not at this point.
So, the short of it is that there is a decent chance of interior portions of New England seeing accumulating snow. Areas closer to the coast and at lower elevations have a lower chance of seeing the most snow at this time with potential rain/mixing issues.
WPC probability of impactful winter weather for Tuesday morning. Areas shaded in darker green have the higher probability:
There could also be a period of strong winds at the coast. With tides still astronomically high early next week, we'll need to watch the coast. With such large differences in both track and timing, it's impossible to put any kind of threat level on coastal flooding at this time, but this will need to be watched.