Forecast discussion: At the moment, Boston is seeing mostly sunny skies, thanks to a very weak area of high pressure. A weak low over Pennsylvania will bring mostly cloudy skies later tonight, with a passing snow shower or two. As we go into Monday, we will see more clouds than sun, and a frontal boundary coming out of Canada will bring the threat of some snow squalls during the evening commute. Any snow showers will end early Tuesday morning. The higher elevations may see an inch by the time we wake up.
The second front will also bring down some very cold Arctic air to much of the eastern U.S. for the next several days. Temperatures will struggle to reach 20 degrees on Tuesday, and only the lower teens on Wednesday. Overnight lows will be in the single digits. This will not be like the polar vortex we received a few weeks ago, but wind chills will be dangerous, as well as leaving exposed skin to the elements.
On Tuesday night, a low pressure system develops well offshore of the eastern U.S. However, if we have a northeast wind, the south coast, Cape Cod, and the Islands will see some snow showers Tuesday night into Wednesday morning. The models bring the moisture back over the interior parts of the state, but they have been very inconsistent from run to run. So, I will leave it in the forecast once again, until I see tomorrow’s model run.
We will clear out by Wednesday afternoon, with another bitterly cold night. Temperatures will slowly rise by Thursday, as a quick moving Alberta Clipper brings the chance for more snow showers Thursday night into Friday morning. Much of the snow showers Thursday night will be along the coastline. High pressure builds in temporarily for Friday, bringing us mostly sunny skies. Overnight lows Friday night only falls into the middle teens.
As we approach next weekend, a developing low just offshore of Long Island will bring some possible snow showers by the middle of Saturday morning. They will persist into early Sunday morning, before a high pressure system returns some sunshine for the rest of the day. After reaching the lower 30’s on Saturday, we will be a little cooler for daytime highs, with highs in the middle to upper 20’s.
72 hour forecast:
Tonight: Partly to mostly cloudy with a passing snow shower. We will see a low of 28.
Martin Luther King Jr. Day: Partly sunny with a high of 39 with temperatures dropping throughout the afternoon. There may be some passing rain showers during the evening commute. Winds will come from the west-southwest at 14-18 mph.
Monday night: Mostly cloudy and colder with snow showers ending by 1 a.m. and a low of 14. Winds will turn to the northwest and diminish to 9-12 mph.
Tuesday: Overcast and much colder with possible snow squalls by the evening commute. The mercury will only rise to 19 degrees.
Tuesday night: Mostly cloudy and very cold with a low of 6. Light snow remains possible through the evening.
Wednesday: Light snow ends by mid-morning, and becoming partly sunny with a high of 14.
Wednesday night: Partly cloudy with a low of 8.
Thursday: Partly sunny with possible snow showers in the evening. Highs 19-22, lows 8-11.
Friday: Snow showers for the south coast during the early morning, with mostly sunny skies by mid-morning. Highs 20-23, lows 15-18.
Saturday: Cloudy with snow showers by mid-morning. Highs 33-36, lows 17-20.
Sunday: Snow showers end in the early morning, with partly to mostly sunny skies. Highs 25-28, lows 12-15.