New England's pattern of persistence continues to roll along. Since the start of the new year, New England has been controlled by a large upper-level low meandering around the Canadian Maritimes. This storm system, which is the remnants of the one that passed through New England on New Year's Day, has grown to be very strong, which has allowed the winds to continue to whip over New England. This system will finally begin to move away for good later this week.
Until it does, though, the region remains in a ridge-trough holding pattern, with New England on the edge of the trough while a ridge sits to the west. The tight pressure gradient between the high to the west and the low to the east is providing this persistent wind. With blocking in place, these features refuse to move (for now), leading to a copy/paste forecast each day.
This lack of progression within the large-scale patterns will result in winds once again gusting in the 35-45mph range with highs once again in the teens north and 20s south. Scattered snow showers will once again develop for the northern tier of the region. This can be copied and pasted for Thursday as well.
With the upper-low hanging around to New England's northeast, it has kept the region under broad cyclonic flow. This has resulted in long-duration upslope snow shower events for the mountains with puffy clouds and scattered flurries for the rest of the region. Subtle disturbances have been rotating around the trough, creating an uptick in snow showers at times. Wednesday will be one of those times as a shortwave and cold front push through the region.
This will bring a reinforcing shot of cold air to the region, resulting in air temperatures topping out a notch cooler than yesterday (though it will hardly be noticed as the wind chills will be similar, anyway). Snow showers across the north and mountains will likely become most widespread this afternoon and evening. A few rogue showers or flurries may be able to push into central and southern New England through tonight, but the dry air will make it difficult to reach the surface.
Below: NAM showing potential weather from around noon today through noon tomorrow:
Snow showers across the north will be light and generally scattered around (outside of the mountain slopes and summits). This will result in minimal accumulations for the northern tier. Most communities will likely see 1-3 inches of new snowfall through Thursday. The northern Green Mountains may be able to pick up another 4-8 inches. Given the cold air, snow will be very light and fluffy. Snow ratios yesterday were observed as high as 35:1. A typical snow ratio in New England is around 8-10:1, so 35:1 indicated very dry and light snow.
This has been ski country's dream setup with nearly constant upslope snow showers since the weekend. Killington Resort has reported seven inches of snow over the last two days and over two feet over the last week. The light and fluffy nature of the snow has been welcome, as well.
This pattern of persistence will begin to break down around Friday. The large-scale setup finally begins to shift eastward with the upper-low over the Maritimes exiting for good and the ridge of high pressure sliding eastward. This will bring a very gradual slackening of the winds starting Thursday night. By Friday, winds will remain breezy, but not nearly to the point of Tuesday through Thursday. The growing influence of the ridge will help shut down the snow showers as well. Temperatures will rebound, climbing a notch warmer as well.
As for the weekend storm, trends continue to point toward less interaction between the northern and southern stream systems. This minimal interaction favors the moisture-rich southern stream system getting suppressed to the south of the region, passing well outside the benchmark. A bulk of snow shower activity this weekend will come from the weaker and less moist northern stream energy. This will likely result in lighter snow (maybe a wide swath of a couple inches) through the day Saturday.
This past Sunday, we published an article specifically saying there's no need to get worked up about a potential snowstorm a week in advance based solely on a couple snapshots from operational model runs. We noted many ensemble members were not on board with a direct hit and even some major operational models weren't interested in the idea.
While higher impacts from this system can't be ruled out until the storm begins to take shape over Texas tomorrow, trends are steadily moving toward a low impact event moving well offshore of New England.
After this storm exits, it will re-open the door for colder and windier weather for much of next week once again (not that a major warm-up is coming this weekend). Overall, this is shaping up to be a consistently cold January, something New England hasn't really seen in a few years.
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