Forecast discussion: A weak high pressure ridge will be breaking down this evening, as a low pressure system over central Canada brings a cold front all the way south to southwest Texas. But, we will feel the warm front first, as temperatures around eastern Massachusetts reach the middle to upper 50’s.
The warm front at the moment is in central New York, and will push into Southern New England early Wednesday morning. We will also see some scattered rain showers, as well as slowly increasing winds. The pressure gradient between the incoming low and the outgoing high pressure system will tighten. When the pressure gradient tightens, this helps create stronger winds in the upper atmosphere, which comes down towards the surface. We may even see wind gusts of 40 mph Wednesday afternoon. For this reason, the National Weather Service has put out a High Wind Watch for all of eastern Massachusetts, including the Cape and Islands, from 6 p.m. Wednesday night until 11 a.m. Thursday morning. The strongest winds will be Wednesday evening, as the cold front begins to push through the region.
Also, during early Thursday morning, you may even hear a rumble of thunder. Due to the very warm air, conditions in the upper atmosphere will be unstable, and we could see some cumulonimbus clouds form. By Thursday afternoon, colder air behind the front will return, and our temperatures will fall quickly. Our winds will diminish as well, as the front pushes offshore.
On Friday, a quick moving low pressure system may help produce some snow showers through the morning and afternoon. The precipitation shield will be east of us by Friday night. A weak high pressure ridge will return some sunshine on Saturday, but temperatures will struggle to reach the freezing mark.
As we move into Sunday, an Alberta Clipper system will push through New England, and we will see some accumulating snowfall before Sunday evening. Another clipper system will quickly push through Monday evening, and stall just to our east. The snow may change over to rain by the afternoon, if enough warm air pushes over the state. At this time, my confidence in the forecast for Tuesday is quite low.
72 hour forecast:
Tonight: Cloudy with rain showers and patchy fog. We will see a low temperature of 32 at midnight, before temperatures increase towards sunrise.
Wednesday: Scattered showers, windy, and milder with a high of 57. Winds will come from the southwest at 15-20 mph with gusts as high as 40 mph.
Wednesday night: A steady light to moderate rain and windy with a low of 47. There may even be an isolated thunderstorm. Winds will come from the south-southwest at 25-30 mph with gusts of 50 mph.
Thursday: Moderate rain ending in the early afternoon with a high of 52. Temperatures will fall by the early afternoon.
Thursday night: Partly cloudy and much colder with a low of 26.
Friday: Cloudy with scattered snow showers and a high of 33.
Friday night: Mostly cloudy with a low of 20.
Saturday: Partly to mostly sunny. Highs 31-34, lows 20-23.
Sunday: Light snow through the day. Highs 33-36, lows 22-25.
Monday: Becoming cloudy by the late afternoon with evening snow showers. Highs 35-38, lows 25-28.
Tuesday: Possible light to moderate snow changing to rain. Highs 35-38, lows 21-24.