Here comes the next winter storm, and this one will have a one-two punch with it for much of the area, though some areas south of Boston may not see much from the second punch. This will take place as low pressure west of New England redevelops over New Jersey, moves northeastward, then intensifies rather rapidly just as it passes Cape Cod and moves into the waters just east of southern New England through Tuesday evening. The solution I am going with is slightly colder than what I had on the last update, which will be reflected by less mix/change in areas north of the Mass Pike, where cold air is entrenched at all levels and will be made even a bit colder due to precipitation falling into dry air and resulting in evaporational cooling. Precipitation starts as snow everywhere late this evening, at least by or shortly after midnight it should be snowing in all locations and snowing moderately to occasionally heavy during the overnight hours into the morning commute. Toward the end of this first burst of heavier precipitation a mix/change line to sleet/freezing rain/rain will appear on the South Coast and progress northward toward the Mass Pike where it should come to a halt. As the first area of heavier precipitation departs during the morning, some mixing may occur further north. As a second area of moderate to possibly heavy precipitation moves in later in the day into the evening, it will fall as snow in areas north of the Mass Pike and rain to mix to snow elsewhere as the changeover line goes back to the southeast. This will result in some additional accumulation of snow.
Snow will accumulate most rapidly in all areas during the early morning hours of Tuesday, more slowly to not at all during the late morning to mid afternoon of Tuesday because of lighter precip, mix, or rain in some areas (south). Another period of accumulating snow late Tuesday afternoon into Tuesday night will be most likely along and north of the Mass Pike to start then include most other areas again for a while later (although it may be heaviest to the north so impact may be less to the south).
Unfortunately, the 2 heaviest periods of snow may be occurring during both commutes. But better news: no significant coastal flooding as winds will not be as strong as recent storms, nor are astronomical tides very high. There may be some minor splashover and beach erosion on east-facing shores at high tide times just before dawn and in the early evening on Tuesday.
Snow accumulations for the entire event: 1-3 inches Cape Cod, Islands, South Coast. 3-5 inches southeastern MA to central RI, 5-10 inches northern RI through the remainder of eastern MA out to about I-495 and up to the NH Sea Coast. 10+ inches north of I-495 including the remainder of southern NH.
Beyond this event, the cold and somewhat unsettled pattern continues. We’ll watch for an ocean storm that may graze the region Thursday night but it has to be watched in case it develops a little closer than currently expected. Another storm later in the weekend is expected to stay JUST far enough south not to have any significant impact but should also be watched should it end up a little closer.
Forecast for southeastern New England…
TONIGHT: Overcast. Snow develops southwest to northeast between 9PM and 1AM, becoming moderate to heavy at times overnight, mixing with sleet/ice/rain South Coast after 4AM. Lows middle 20s to lower 30s north to south. Wind E 5-15 MPH.
TUESDAY: Overcast. Snow except mix to rain line moving northward toward the Mass Pike morning-midday, then all precipitation getting lighter for a while into the afternoon before picking up again later in the day as snow north and mix changing to snow further south. Highs upper 20s southern NH to middle 30s South Coast of MA/RI. Wind E 10-20 MPH with gusts around 30 MPH inland and 15-30 MPH with gusts 40-45 MPH at times coast, shifting more to the NE with time.
TUESDAY NIGHT: Cloudy through midnight with snow except mix to snow southern areas, tapering off late, followed by breaking clouds. Lows in the 20s. Wind NE to N 10-25 MPH with higher gusts.
WEDNESDAY: Variably cloudy. Slight chance of light snow showers. Highs in the 30s. Wind NW 15-25 MPH and gusty.
THURSDAY: Mostly cloudy. Period of snow possible at night especially eastern areas. Low 28. High 38.
FRIDAY: Mostly cloudy. Low 27. High 39.
SATURDAY: Partly sunny. Low 24. High 40.
SUNDAY: Mostly cloudy. Watching storm to the south. Low 24. High 40.
MONDAY: Partly sunny. Low 22. High 38.