Forecast discussion: After several days of below normal temperatures, Boston almost reached freezing temperatures Thursday afternoon. Officially at Logan Airport, we reached 30 degrees. For the first time in four days, temperatures will go above freezing on Friday. It will become much warmer this weekend, but we can expect a wet weekend as well.
High pressure will be slowly moving offshore this evening. As winds slowly turn to the south, we will see more moisture move over the region. Despite the high’s ridge, a weak disturbance will bring some snow showers during the mid to late morning on Friday. We may see a coating to a half inch, before temperatures make the atmosphere turn the precipitation to scattered rain showers in the mid to late afternoon. A developing area of low pressure in the Central U.S. will bring more precipitation, starting early Saturday morning.
As the low moves eastward, it will pick up moisture from the Gulf of Mexico. The precipitation will become heavier as we move into the afternoon and evening. So, if you are heading to Foxboro for the Patriots-Colts game Saturday night, please bring your rain gear. It will be quite wet, and you can also expect some windy conditions.
The rain will taper to showers by early Sunday morning, and all precipitation will end by the middle of the morning. Limited sunshine is expected for the afternoon. Temperatures will remain above normal, with highs in the upper 40’s. We will see more clouds than sun on Monday, with the chance of some scattered showers early Tuesday morning. By Tuesday night, the computer models all disagree on their solutions.
The American model does not develop a low’s center until an upper level trough makes its way above the east coast. A surface low develops Tuesday afternoon, over the Mid-Atlantic, and remains stationary into Wednesday. The United Kingdom model brings a strong low pressure system from the Central U.S. towards the Northeast U.S., creating some heavier rainfall. Finally, the European model develops a secondary low over the Southeast U.S., before it intensifies as it moves towards New England on Wednesday. Right now, my confidence in the forecast after Monday night is very low. I will keep the chance of some rain and/or snow showers in the forecast for Wednesday, as the models do agree the atmosphere will be saturated enough for precipitation. The precipitation shield associated with the lows in each model will be offshore by early Thursday morning.
72 hour forecast:
Tonight: Clear skies until midnight, with increasing clouds during the overnight. We will see a low of 19.
Friday: Partly sunny with possible snow showers in the late morning, followed by scattered rain showers in the afternoon. We will see a high of 39 with south-southwest winds of 5-8 mph.
Friday night: Mostly cloudy with some scattered showers by 4 a.m. and a low of 36. Winds will turn to the southeast at 2-5 mph. Patchy fog is possible.
Saturday: Overcast with showers increasing to moderate rain by the afternoon. We will see a high of 54 with increasing winds by the afternoon.
Saturday night: Rain and windy before midnight, before tapering to showers by 2 a.m. We will see a high of 43.
Sunday: Showers end by mid-morning, with partly sunny skies expected during the afternoon. We will see a high of 47.
Sunday night: Partly cloudy with a low of 33.
Monday: Partly to mostly sunny. Highs 47-50, lows 37-40.
Tuesday: Cloudy with scattered showers by the early morning, but end by noon. Highs 45-48, lows 31-34.
Wednesday: Cloudy with scattered rain/snow showers and cooler. Highs 40-43, lows 25-28.
Thursday: Snow showers end by 2 a.m. with partly to mostly sunny skies. Highs 35-38, lows 19-22.