5:55PM
A disclaimer off the top: This forecast is still a low to medium confidence one as of late Tuesday afternoon because of the factors going into the amount of precipitation and the placement and movement of a rain/snow line regarding the upcoming storm. I will be monitoring the situation and issuing updates as often as needed.
** Update issued at 7:25AM Wednesday **
A major storm coming off the Mid Atlantic Coast Wednesday will track pretty far south to southeast of New England (in terms of the center), but it is such a large circulation that it will impact all of southern New England with precipitation including some significant snow. The greatest impact from this event will likely be wind and tide related, along with tree and power line damage where the heaviest snow falls, as it will be on the heavy/wet side due to marginal temperatures.
The break-down…
TIMING: 3-day event, starting Wednesday as clouds thicken and winds increase from the east to northeast. Precipitation arrives Wednesday night and is likely rain at the coast and a mix inland. Heaviest precipitation occurs Thursday and Thursday evening in the form of mostly snow inland and mix transitioning to snow at the coast, lastly over Cape Cod and the Islands. Precipitation lingers into Friday morning and may go to mix/rain coast and just inland as it lightens up but will probably remain as mix/snow further inland.
WIND: Winds start out east to northeast during the day Wednesday and become mostly northeast Wednesday night then shift to mostly northerly Thursday and Thursday night into Friday. Strongest winds take place during the day Thursday but they will be pretty strong from Wednesday night through the early hours of Friday. Peak gusts will be over 55 MPH across Cape Cod and the Islands, 45-55 MPH in the remainder of coastal RI, MA, and NH, and 35-45 MPH over inland areas except 45-55 MPH in some higher elevations.
TIDES: Moderate coastal flooding and beach erosion will be most prevalent 2 hours before through 2 hours after the high tides especially Thursday through early Friday along east-facing and especially north-facing shores. Scituate and Sandwich MA may see some of the worst of the flooding.
SNOW: This is subject to change because of the difficulty in forecasting positioning and movement of rain/snow lines, but a first guess…0-2 inches Cape Cod & Islands from east to west, least on the outer Cape & Nantucket, 2-4 inches remainder of eastern MA to the east of I-95 including the immediate coast of NH and coastal RI with up to 5 inches in some higher elevations, 4-8 inches near and west of I-95 with 8+ inches possible in higher elevations. This snow will be occurring over a fairly long period of time, so it may limit road impact to some extent, though expect difficult travel in areas of heavier snow that occur.
POWER OUTAGES: These possible from heavy wet snow accumulating on trees and power lines, especially where 4 or more inches of snow falls. They may also occur due to wind damage especially in coastal areas.
After the storm…
Forget the significant warm-up for the weekend as a north to northwest flow will dominate Saturday and be reinforced Sunday, keeping it in the 40s for daytime highs (though sunshine at times, especially Saturday afternoon & Sunday morning will feel nice).
More unsettled weather arrives early next week but not looking like a big storm at this time.
Forecast for southeastern New England (southern NH, eastern MA, and RI)…
WEDNESDAY: Cloudy. Spotty light rain or drizzle possible during the morning and again late in the day. Highs around 40. Wind NE to E 10-20 MPH gusting around or over 30 MPH mid afternoon on especially near the coast.
WEDNESDAY NIGHT: Overcast. Rain to mix coast, mix to snow inland. Lows in the 30s. Wind E to NE 15-25 MPH inland, 25-35 MPH coast with stronger gusts (see above).
THURSDAY & THURSDAY NIGHT: Overcast with snow inland, mix to snow coast. Most of the accumulation of snow takes place during this period (see above). Temperatures holding in the 30s, coldest inland. Wind NE to N 15-35 MPH with stronger gusts (see above).
FRIDAY: Cloudy. Lighter precipitation – snow to mix inland, mix/rain coast with little additional snow accumulation. Highs around 40. Wind N 10-30 MPH, strongest coastal areas.
SATURDAY: Mostly cloudy AM. Partly cloudy PM. Low 30. High 44.
SUNDAY: Mostly sunny AM. Partly sunny PM. Low 31. High 45.
MONDAY: Cloudy. Low 32. High 42.
TUESDAY: Mostly cloudy. Rain showers possible. Low 38. High 49.