As we begin to enter meteorological spring, temperatures will begin a battle of the seasons with up and down numbers over the next several days. For today, a cold front will push into northern New England. This front will slow down and likely stall out across southern New England later in the day. A modest push of colder air will occur behind this front, with afternoon highs not rising much from morning lows across the north. Central and southern New England will see highs rise several degrees as the cold front slows down.
Saturday will see a surge in temperatures for southern and central New England as an Alberta Clipper's warm front lifts into the region. A surge of mild air will occur on the south side of the clipper's track, especially for southern New England, who will be firmly within the system's warm sector.
Alberta clippers often swing the door wide open for Arctic air to enter New England as they depart, and this one is no exception. Cold and breezy conditions will return for a two day bout for Sunday and Monday as a strong cold front is dragged across the region. Much of New England will see high temperatures 20-25+° lower on Sunday than on Saturday.
Temperatures currently look to moderate back toward average by Tuesday of next week before another surge of warmer air will be possible ahead of the next storm system. The storm looks like an inside runner with a strong southerly flow developing ahead of a cold front for New England. The battle between winter and spring temperatures is arriving right on time as we enter into March.
A major factor in these up and down temperatures through the weekend will be the incoming Alberta Clipper and its attendant frontal boundaries. This system will zip through New England, bringing another quick round of rain and snow showers. The system will move through at a rapid pace, bringing a round of light snow to the north of the track and a mix of rain and snow showers to the south of it.
Alberta Clippers tend to deposit their most snow on the north side (and near the center) of the system. Lighter precipitation and lesser amounts are often seen moving southward, away from the storm's center. With a track close to the Canadian border, the jackpot zone for the storm will be just north of New England, into Quebec, where a swath of 5-8 inches will be possible. In New England, a jackpot zone of 3-6 inches is likely across the northern third of the region extending into the White Mountains.
Being well south of the track, southern New England and into southern Vermont and New Hampshire will see much lighter and more scattered precipitation for a shorter period of time Friday night and Saturday morning. This will result in minimal, if any, snow accumulations.
The clipper's main batch of precipitation ahead of the system's warm front will likely push into western New England late this evening and steadily move eastward through the overnight hours. By the pre-dawn hours, a changeover to a mix and plain rain will likely occur across southern New England and southern New Hampshire. A dry slot will likely move into the region from west to east through Saturday morning, resulting in much more spotty showers across the region after daybreak.
Below: HRRR showing potential weather around midnight tonight (1st image) and around daybreak Saturday (2nd image):
Spotty snow and rain showers will continue throughout the day, though many areas will likely end up mainly dry for much of Saturday. In the afternoon, the greatest forcing for showers will come along the system's trailing cold front. A broken line of showers may develop along this front.
There will be the potential for snow squalls to be embedded within this line as snow squall parameters appear to be elevated. The combination of frontogenesis and surface instability will lead to this threat. There should be sufficient moisture remaining for precipitation to develop along the front. Snow squalls will likely be limited to the higher terrain (including western and maybe central Massachusetts) as surface temperatures will likely be too high in the lower elevations for snow to be pulled all the way to the surface at this point.
Below: GFS showing potential weather Saturday afternoon:
As mentioned at the beginning, this front will be causing temperatures to plummet later Saturday and overnight. Rapid clearing will take place behind the front with overnight lows dropping into the single digits north to teens south. The cold will peak (or bottom out) Monday morning, when wind chills reach near the -30s across the north to the -10s across southern areas.
After Saturday, the next storm to watch will likely come around mid-week next week. All early signs are pointing toward a warm and wet storm with the potential for a soaking rain event as a low pressure system ejects from the Great Lakes. The storm looks like an inside runner with a strong southerly flow developing ahead of a cold front for New England. This could lead to strong winds as well.
Should this come to fruition with a potent low pressure system, significant snowmelt would likely occur across the north along with the rainfall and potential winds. Depending on how the exact setup shakes out, northern areas could see a burst of snow or a mix at the onset. Current timing would have the system moving through from Wednesday into Thursday morning, but this remains subject to change.
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