9:26AM
Not too often you get a snowstorm fitting neatly into a calendar day, but today is one of those times. A wave of low pressure moving west to east and passing south of New England is the cause.
As of 9AM, the heaviest snow has already fallen in some locations north of the Mass Pike and outside Route 95, though it will continue to snow there for several more hours. Light to moderate snow will continue elsewhere with the 2 to 5 inch amounts easily reached in most locations. Some 6 to even 7 inch totals are still possible mainly in areas south of the Mass Pike where heaviest snow lasts longer, and where some enhancement takes place from moisture off the ocean (especially closer to the South Shore). To the north, under 2 inches will fall near the MA/NH border. This is a light and fluffy snow for just about everybody (except a little wetter over Cape Cod). This should be a done deal by tonight as the wave of low pressure heads into the Atlantic and high pressure again builds north of New England.
The remainder is from the previous discussion followed by an updated Boston area forecast.
Sunday, high pressure will continue to hold on to the north of the region, sending a northeast wind into southern New England. This may produce some ocean-effect snow showers. As the high pressure area slides more to the southeast an approaching warm front will provide focus for moisture and warmer air to ride over New England, and with lingering cold air at the ground, the setup for some icing will be in place as rain breaks out due to the warming air aloft. Icing may linger into Monday morning over inland areas where cold air can be tough to dislodge. Areas closer to the coast will warm sufficiently so that plain rain will be falling by Monday morning. Eventually, all inland areas will warm to above freezing so that Monday turns into a rainy day for just about the entire region. Once a cold front crosses the region from west to east Monday night or early Tuesday, drier weather will move in, but this may prompt someone to argue the definition of a cold front since Tuesday will probably turn out to be the warmest day of the next several days. A secondary cold front late Tuesday will introduce colder air for the middle of next week.
Weather for Patriots/Ravens game in Foxboro at 3PM Sunday: Lots of clouds, chance of a snow shower, kick-off temp 33, end-of-game temp 30. Wind NE up to 10 MPH.
Boston Area Forecast…
TODAY: Overcast. Snow of 2 to 5 inches with some 6 or 7 inch amounts possible in areas south of the Mass Pike and near some north-facing coastal areas to the south of Boston. Parts of far northern MA and southern NH will come in below 2 inches. High 22-27. Wind N-NE up to 10 MPH.
TONIGHT: Mostly cloudy. Slight chance of a few lingering light snow showers. Low 15-20. Wind N-NE up to 10 MPH.
SUNDAY: Variably cloudy. Chance of snow showers, best chance closer to the coastline. High 30-35. Wind NE 5-15 MPH.
SUNDAY NIGHT: Cloudy. Chance of snow showers early. Chance of sleet and freezing rain inland and sleet, freezing rain, or plain rain closer to the coast. Low 25-30 inland, 30-35 coast. Wind E up to 10 MPH.
MONDAY: Cloudy. Areas of fog. Rain likely, but some icing conditions may persist over inland lower elevations during the morning. High 42-47 but probably not until late day. Winds light E inland areas, SE 5-15 MPH coastal areas during the morning, eventually shifting to S and increasing to 10-20 MPH during the afternoon.
TUESDAY: Variably cloudy. Chance of rain showers. Low 42. High 53.
WEDNESDAY: Partly cloudy. Low 25. High 35.
THURSDAY: Mostly sunny. Low 18. High 36.
FRIDAY: Cloudy. Chance of mix/rain. Low 29. High 42.