Forecast discussion: Once again, high pressure over the Northeast U.S. brought another morning of sunshine to Boston on Friday. However, you probably noticed the clouds increasing throughout the afternoon. This is due to a low pressure system off the coast of North Carolina. The low will be moving to the northeast, but the high will actually protect us from seeing any precipitation tonight. There is the chance of the lower Cape and Islands seeing some drizzle or a passing shower during the overnight hours.
Other than that small fly in the ointment, Saturday is shaping up to be a nice day. We will see limited sunshine at times, but the one thing you cannot miss is the high temperature. I’m expecting the mercury to rise into the middle 40’s. However, the mild air will be brief. A cold front now moving into the middle of the Great Lakes will bring cooler air as it passes over us on Sunday. We may see a brief snow shower during the evening Saturday night into Sunday morning. Otherwise, we will see mostly sunny skies and temperatures only reaching the middle 30’s. Also, don’t forget to move your clocks ahead one hour at 2 a.m. Sunday morning.
As we head into Sunday night, a weak low pressure system will come down from Canada and into northern New England. This disturbance may bring some possible snow showers early Monday morning until the beginning of the evening commute. We will see dry weather into Tuesday, but the middle of the week shows a very important storm system bringing more winter misery to eastern Massachusetts.
The low in question actually forms over western Kentucky early Wednesday morning, and gains some upper level dynamics. We will begin to see the first snowflakes just before the start of the evening commute. The hardest question to answer right now is what type of precipitation we will see. Based on the four computer models I can see, three of the four have the low moving to our south and east. This means a colder solution, meaning we would see all snow or a mix of snow and sleet. The only model showing a warmer solution is the European model. This would show a mix of snow, sleet, and rain. At this time, my confidence in the forecast remains low. Because this forecast is very track dependent, a difference of even 30 miles could be the difference in seeing a wintry mix or staying all snow.
The computer models do agree that the system will push away from Southern New England by late Thursday afternoon. We will begin the next weekend with mostly sunny skies. However, temperatures will remain well below normal for this time of the year. High temperatures on Friday are only going to reach the middle to upper 30’s. The average high for mid-March is about 42 degrees.
72 hour forecast:
Tonight: Mostly cloudy with a possible shower along the south coast from midnight until 6 a.m. We will see a low of 26.
Saturday: Partly sunny and warmer with a high of 44. Winds will come from the north-northwest at 8-11 mph.
Saturday night: Mostly cloudy with a possible snow shower and a low of 27. Winds will come from the west-northwest at 7-10 mph.
Sunday: A possible snow shower until 9 a.m., otherwise mostly sunny. We will see a high of 37.
Sunday night: Mostly cloudy with a low of 24.
Monday: Mostly cloudy with possible snow showers starting in the morning. Snow showers end by the late afternoon. We will see a high of 39.
Monday night: Mostly cloudy with a low of 32.
Tuesday: Partly sunny. Highs 44-47, lows 30-33.
Wednesday: Cloudy by late morning, with light snow developing around 4 p.m. Light to moderate snow through the evening, possibly mixing with sleet or rain. Highs 35-38, lows 23-26.
Thursday: Wintry mix changing back to light snow through the early morning, before ending by the late afternoon. Highs 30-33, lows 15-18.
Friday: Mostly sunny. Highs 35-38, lows 18-21.