Weather

Here’s David Epstein’s snowstorm forecast

Monday's storm will bring snow, wind, and flooding to Massachusetts.

MA snow forecast
There could be some light accumulation of snow along the coastal plain, but much of it gets washed away by rain. David Epstein


An intense low pressure area will move through New England early Monday and then head up into Canada. This storm will bring all sorts of weather with it, from snow to rain to coastal flooding, and even damaging wind.

The storm will move in around 1 to 3 a.m. Monday. After peaking around sunrise, it will wind down by noon. It’s in this window that we will see the snow, the rain, the wind, and the coastal flooding.

Snow Potential

The snow with the upcoming system is actually the least noteworthy part of the storm. It’s pretty amazing that we’re going to go from having Arctic air in place to temperatures in the 40s.

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When the center of low pressure goes west of Boston, it allows mild maritime air to flow in from the ocean. This means even the coldest air at the onset of the storm can rapidly be eroded and the accumulation of snow is quite light.

The further inland you go the snow will last longer. So, on the map above, you’ll see I have an area of 4 to 8 inches across Worcester County and on into portions of New Hampshire and Vermont. The reason for the wide range is because it will depend on exactly the time of the changeover as to who has the highest accumulation.

Everybody’s going to change over to rain with the surge of mild air. Any snow within 15 miles of the coastline will be gone by the middle of Monday morning, but far inland areas might hang onto some slush. Be sure you remove any snow that is left after the rain as it will freeze rock solid on Tuesday.

Coastal Flooding

There’s a coastal flood warning in effect from about Plymouth northward, including Boston and the North Shore, for the time of high tide during Monday morning. Flooding could be moderate in these areas during that time of high tide which means certain vulnerable roads will likely be closed and there could be beach erosion as well as some potential damage.

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Strong Winds

There’s going to be a burst of wind a few hours before and a few hours after sunrise on Monday. The graph below, which is a summary of a bunch of different models, shows the peak wind arriving right around 7:00 a.m. Along the coastline winds could gust up to 60 mph and this could certainly cause some damage as well as power outages. Inland the winds will be significantly lighter but still busy enough to perhaps create a few problems.

It clears out Monday night and temperatures fall back down to the 20s, as winds start coming from a colder direction. Tuesday is sunny and blustery with highs only in the 20s. After a moderate trend in the middle of the week, more Arctic air will arrive to start the upcoming weekend.

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