Limited Friday morning sunshine will yield to advancing clouds during the afternoon as a spiraling upper level disturbance with strong atmospheric energy drops southeast out of the Central Great Lakes.
Poised to drop south of New England as it moves over the western Atlantic Ocean, this disturbance will spawn development of a new storm center at the surface, east of the mid-Atlantic coast. This is far enough away from New England to spare most of us of direct impacts, but close enough to produce an onshore wind to thicken clouds Friday afternoon; and close enough to drag snow showers and a shield of snow over the South Coast and especially Rhode Island and Southeast Massachusetts overnight Friday night.
With daytime temperatures in the 40s, it’ll be a slow drop in temperature even in the areas that see steadiest precipitation, with Cape Cod snowing longest and strongest, accumulating one or two inches overnight, with highest amounts on grassy surfaces. On the Island of Nantucket, some of our guidance is cranking out half a foot of snow!
Our First Alert team is calling for closer to three inches, but willing to contend the forecast for the island is very difficult with ocean temperatures just above 40°, daytime air temperatures in the 40s and only a slow feed of colder air overnight.
As for roads, they’re likely to start wet on the Cape, but after enough snow falls, roads may cool enough on the Mid and Outer Cape for some slick spots after 1 or 2 a.m. Farther northwest, only a coating to an inch of snow is expected in southeast Massachusetts and Rhode Island, with almost nothing from the southern suburbs of Boston points north, save for a coating to an inch in the northern mountains with a separate Friday evening disturbance.
The more widespread impact of the strengthening ocean storm will be an increasing wind, blowing from the north with gusts over 40 mph in southeast Massachusetts Friday night and widespread gusts over 40 mph in New England Saturday, coupling with highs around 40° to create a wind chill near 30° at the warmest time of day, making for a blustery day even as morning clouds give way to sun. Moderation arrives Sunday – into the 50s for most of us – with temperatures pushing into the 60s Monday and Tuesday.
Eventually, the chance of showers returns to the forecast for the middle and end of next week, possibly lingering into the start of next weekend at the end of our exclusive First Alert 10-day forecast after several dry weekends.