The first measurable snow of the season could blanket the Boston area and other parts of Southern New England next week, with a nor’easter forecast to brush the region Tuesday night into Wednesday.
The Northeast’s active weather pattern on Monday is expected to continue into Tuesday when a new storm system, the nor’easter, approaches. The track of this nor’easter will determine what type of precipitation we get, snow or rain, but some areas of New England could likely see their first decent amount of snowfall of the season.
If you’re wondering about the potential wintry weather, it is still very early to forecast timing, snowfall totals, and where roughly the rain-snow line will fall. They’re just guesses at this point. Right now, that weather system is still coming out of Alaska, so the data is sparse and will get better over the weekend as it approaches the West Coast. I usually hesitate to talk too much about a storm that’s several days away, but I also realize that folks want to know what the possibilities are for planning purposes.
But I am comfortable showing you a probability map. The map below gives us the probability of at least an inch of snow, according to the European ensembles. To refresh what an ensemble is, it’s a series of forecasts made by one model with minor tweaks. Think of it like following a recipe. In one version of the recipe, you might sift the flour and in another, you don’t. It’s the same recipe, but you get a little bit of a different outcome.
This map shows the probability of 1 inch or more of snowfall throughout New England. The red area (covering parts of Central and Western Mass. and Northern New England) has the highest likelihood of seeing at least an inch of snow.WeatherBELL
As I noted earlier, the key to what type of weather we in New England will experience Tuesday into Wednesday will be dictated by the track of the storm. If the storm ends up hugging the coast, then warmer air would flood in from the Atlantic, which is still relatively mild this time of year, we would mostly see rain east of I-495.
But if the storm is a little farther offshore, then the rain-snow line will be closer to the coastline and even Boston could see its first measurable snow this season. Climatologically, it’s less likely that the coastal plain sees anything other than a cold rain or a wet mix, but Boston may end up with some accumulating snow if the storm tracks just a bit more offshore, keeping the cold air in place. Parts of the polar vortex are expected to blast the US with frigid air over the next couple of weeks, but fortunately, New England will stay on the fringe of this cold stretch and should only see moderately below-average high temperatures in the 40s and upper 30s.
It’s too soon to determine where the rain-snow line will fall or what areas will see more snowfall than others but just know that your plans could be disrupted on Tuesday. Of course, it’s still several days out and there will be more on this later in the weekend. Stay tuned!
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