The temperature was falling below freezing throughout Southern New England Sunday evening. In many spots, it may not make it back above freezing all week long. The first surge of chilly air moving in out of Eastern Canada will drop the temperature into the upper teens to low 20s by dawn Monday. It will become mostly cloudy by early Monday afternoon, and some light snow may break out during the late-afternoon or early-evening. Occasional light snow and snow showers are likely Monday night as a storm develops southeast of Nantucket.
A weather feature known as a Norlun trough will develop to the west of the storm. This axis of locally heavy snow is likely to be north of Boston, and probably in Eastern Maine or far Southeast New Hampshire. Those areas may pick up 6-12″ of snow Monday night into Tuesday. in Southern New England, the totals will range from 1-2″ in Western CT and MA, to 2-4″ in RI and interior SE MA. 3-6″ of snow is possible in far Eastern MA. The snow will be drier, lighter, and fluffier than some of the accumulating snows so far this winter due to temperatures in the 20s.
The accumulating snow will end in RI by dawn Tuesday. Some lingering snow showers are possible in Eastern MA on Tuesday. It will be a partly to mostly cloudy day with highs in the 20s. Bitter cold air will move in Tuesday night. The temperature will drop into the single digits, and may reach zero in some inland locations. Highs will not make it out of the teens under partly sunny skies in most spots away from the coast on Wednesday afternoon. Thursday also looks bitter cold with similarly frigid temperatures and partly sunny skies.
Another storm will take a run at Southern New England late in the week. Right now, it looks like there is a decent chance of a moderate snowfall from a relatively fast-moving system sometime between Friday and Saturday.