After long, dry stretches in January amid persistent cold temperatures, the overall pattern is set to become much more active. This started in earnest this morning with the scattered snow showers and squalls. It will continue with multiple systems pushing through New England from now through at least early next week.
Following today's strong frontal passage, an Alberta Clipper will zip through New England tonight into Wednesday. The center of the storm will likely be over the Great Lakes early Wednesday morning, but the system's warm front will be lifted into New England ahead of it, providing forcing for a period of light snow. A weak coastal low will likely develop in the Gulf of Maine as the system moves through Wednesday morning.
The shield of snow will likely enter into western New England around midnight before sliding eastward through the pre-dawn hours. As the morning continues, the shield of snow will likely begin to lift northward with the bulk of the precipitation likely out of southern New England by, or just after, sunrise. The greatest forcing for snow will be north of the low pressure system, so snow showers will likely last longer across northern New England.
Below: HRRR showing potential weather in the pre-dawn hours Wednesday (1st image) and around mid-morning (2nd image):
By early Wednesday afternoon, the quick-moving clipper (the re-developed surface coastal low) will likely be located around Downeast Maine. The trailing upper-level trough will swing through New England in the afternoon and evening, renewing chances for some scattered snow showers (or even some squalls) to re-develop across New England, but this won't be a shield of widespread snow like the morning.
Below: HRRR showing potential weather around mid-afternoon Wednesday:
Most Alberta Clippers are on the weaker side and move through the region quickly, bringing a low-impact snow event to New England. Every once in a while they can become more potent and bring a decent thump of snow, but this will not be one of those times. A widespread 1-3 inches of snow is likely across New England with a "jackpot" over the Greens. With the best forcing to the north, the higher amounts will likely end up across northern New England, though the ceiling on what "higher amounts" will be is pretty low.
While this is a pretty straightforward system, the re-developing coastal low over the Gulf of Maine will be the one thing to watch. Some signals do point toward this low developing into an inverted trough, which would allow for a brief period of enhanced snow around southwest Maine. This could potentially boost totals slightly there, especially factoring in the fluff factor that will be present with this one.
Alberta clippers often swing the door wide open for arctic air to follow them. This one is no exception as another decent (albeit brief) Arctic blast swings down behind the clipper's cold front. A period of gusty winds will accompany the Arctic air, with gusts of 25-40mph from Wednesday night through Thursday.
Another northern stream system with limited moisture will pass to New England's north Thursday night into Friday. This will lift a warm front across New England, bringing a quick end to Thursday's Arctic blast. The limited moisture with the system combined with residual dry air over New England will make precipitation difficult for most with this system. Any snow showers will likely be contained to the northern tier of New England Friday morning. For everyone else, this system will result in a milder day compared to Thursday.
While the northern stream system zips by earlier on Friday, a more moisture-rich southern stream system will approach New England from the south. There remains an unusually large spread in potential tracks at this point in the forecast period. This uncertainty can likely be attributed to the general split-flow regime New England has been under. This occurs when the northern and southern streams remain generally separated, keeping northern and southern stream systems independent of each other.
This is where the uncertainty comes in. With a northern stream system moving north of New England earlier Friday and a southern stream system approaching later Friday, the timing of both will determine the impacts Friday afternoon into Saturday. In short, the northern system could help deflect the southern system to the south. How far south, or if this deflection happens at all, will determine the northward extent of precipitation during this time as well as precipitation type. The two systems will not phase at all.
Major models remain in three separate camps as of writing this morning. The Euro presents a northern outlier. This would push precipitation northward through much of New England. This would also push a rain/snow line further north as well, leading to more rain across southern New England and mixing issues elsewhere. The GFS runs the system further south, but not far enough to preclude widespread precipitation. The rain/snow line would be further south as well. The CMC pitches a near shutout for New England with the system staying well south.
Below: The three model runs (Euro, GFS and CMC) described above:
Just a quick note, the traditional Euro's AI counterpart AIFS has the system passing well south of New England as of Tuesday morning's runs. This is a major difference from the traditional Euro model's run showing the northernmost solution. We'll get to see which one was more accurate at this stage.
The timing of the northern stream clipper will determine much about the track. Should it kick through faster Friday morning, it could leave the door open for a more northerly track. This would also allow the system's cold front to clear the region, allowing for colder air. Should the clipper move through slower, the attending cold front could help push the storm to the south. This colder air filtering into New England will play a big role in where snow sets up as opposed to mixing and rainfall.
Below: Current Weather Prediction probability of winter weather impacts Friday morning to Saturday morning:
The pattern does stay active after this system with another poised to move through on Sunday into Monday. Like the Friday night storm, there will likely be questions about a rain/snow line across New England. With the uncertainty surrounding Friday night, we'll leave this one at that for now.
Below: Current weather map for Monday morning (February 3):
One last note about this active forecast is the changeable temperatures. With a succession of ridges and troughs punching through New England, it will lead to whiplash with up and down temperatures. With Arctic intrusions quickly being replaced with warm air advection and vice versa, temperatures will be all over the place through at least early next week.
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