I’ve just spent a month teaching meteorology to a bunch of undergrads. One of the topics we talked about is the coastal front and what a difficult part of forecasting it is. The coastal front is the dividing line between marine air and colder land air that often sets up during a coastal storm in winter. It’s a notoriously fickle boundary. If it moves inland a little further you end up with more rain than snow, and that’s what happened this afternoon. This doesn’t mean the storm is over, it just means that the heaviest snow will not be occurring in Boston.
Where we do have snow it will pile up over 6 inches, and there could be a foot or more in the colder areas, especially well west of Route 128, but also into the Route 495 and northern Worcester County area. If you drove from Boston to Worcester you would definitely experience much different weather conditions this afternoon.
The storm is tucked east of New York City and continues to pinwheel moisture inland two hours south. It’s because of the position of the storm that it’s moving too much milder marine air into Eastern Massachusetts and Rhode Island to produce snow conditions. This could also impact the Maine coastline, where it’s possible a change to rain occurs overnight.
How hard will it snow?
In some areas, the snow will fall at 2 inches per hour, yielding half a foot in a very short period of time. This will make any travel very difficult. Winds will increase this afternoon and become quite gusty. Since temperatures are going to be at or a little above freezing, plus wind, the biggest issue I see is the chance of power outages. This could be particularly exacerbated in areas that receive the heaviest and wettest snow.
Wondering if this could become a blizzard?
A blizzard is a storm with a visibility issue with quarter-mile visibility and winds 35 miles per hour or higher for three consecutive hours. Although we may see some blizzard-like conditions, especially along the coastline, I don’t expect this storm to be an official blizzard.
How much snow can you expect in your area?
Looking at the snow map below, you’ll see a range of expected snowfall for Massachusetts up to 18 inches. As warmer air moves up the coastline, the snow will change to rain, so I’ve lowered my forecasted snowfall for Cape Cod and the eastern coastline. If you live within 5 to perhaps 10 miles of the coastline, you should expect snowfall amounts to vary significantly. The warm marine air is going to limit the snowfall in these areas.
When will the heaviest part of the storm end?
I expect most of the accumulating snow to come to an end between 8 and 11 p.m. from the southern interior suburbs to areas west of Route 128. It will go a little longer as you move north of Route 2, but even there the heaviest will be over around midnight. The rain might even push out to Route 495 before it all comes to an end, making the snow harder to remove.
Will there be coastal flooding?
Coastal flooding will be minor, but some short roads are likely going to get closed at the time of high tide later this evening. There could be additional minor flooding Tuesday at the time of high tide.
The storm will meander to the south on Tuesday before spinning itself to death as it moves out to sea on Wednesday. There could be some more light precipitation tomorrow or Wednesday in the form of rain or snow, but nothing significant.
The clouds will hang tough on Wednesday, and there actually could be some more snow showers. The good news: by Thursday, sunshine will return with seasonably chilly temperatures.