Forecast discussion: If you happened to be out and about around eastern Massachusetts on Sunday, you would think it was early May. Clouds and east winds kept our temperatures quite cool, with the high only reaching 70 degrees in Boston. The temperature actually increased as some sunshine came from out of the clouds to warm the mercury by the early afternoon. However, as east winds increased, the temperature began to fall.
The cooler weather is due to a frontal boundary that is parallel to the coastline of Southern New England. However, there was not a lot of moisture in the atmosphere to create any shower activity. As we go through the overnight, there may be some patchy drizzle or mist, as the dewpoint and temperature come close to one another. This will allow the creation of patchy fog into tomorrow morning.
As we go through the work week, the frontal boundary will remain in place. So, we will see partly sunny conditions into Wednesday. However any sunshine will help create some instability in our atmosphere, which will help create the risk of showers and thunderstorms. The best chance will be by the early afternoon, as we move closer to seeing the high temperature for the day.
By Wednesday, a cold front now north of the Great Lakes will move into New England. It will start in Northern New England, but move south during Wednesday night. This will help create the risk for some showers and thunderstorms into early Thursday morning. By Thursday, a high pressure system coming out of Canada will move west of New England. This high will become quasi-stationary, giving us sunny conditions into the following weekend. However, thanks to an upper level trough, we will not see any hot weather we are so known for in August. High temperatures will remain in the upper 70’s to lower 80’s.
Finally, it is time to give an update on Tropical Storm Bertha. As of 5 p.m. EDT, Bertha was centered at 23.3N 73.2W, or about 95 miles east-southeast of San Salvador. Maximum sustained winds are at 45 mph, and is moving northwest at 18 mph. The system is east of the Bahamas, and is forecast to begin turning more to the north in the next 24 hours. As of now, the track keeps the system away from the east coast. However, the system will continue to intensify, bringing increased seas and swells towards the mainland. By early Wednesday morning, it will be strong enough to be considered a hurricane. So, we may begin to see strong rip currents around our east facing beaches by Tuesday evening.
72 hour forecast:
Tonight: Cloudy with patchy drizzle and patchy fog. We will see a low of 63.
Monday: Partly to mostly sunny with the risk for afternoon showers or thunderstorms. We will see a high of 81. Winds will come from the south-southeast by the afternoon at 7-10 mph.
Monday night: Mostly cloudy and patchy fog with a low of 67. Winds will come from the west-southwest at 4-7 mph.
Tuesday: Partly sunny with the chance for some afternoon showers/thunderstorms. We will see a high of 82.
Tuesday night: Mostly cloudy with a low of 67.
Wednesday: Partly sunny with the chance for showers/thunderstorms, starting in the late morning. We will have a high of 79.
Wednesday night: Showers end during the early morning. We will see a low of 64.
Thursday: Early morning showers become partly to mostly sunny skies. Highs 78-81, lows 61-64.
Friday: Mostly sunny. Highs 78-81, lows 61-64.
Saturday: Mostly sunny. Highs 79-82, lows 62-65.
Sunday: Mostly sunny. Highs 79-82, lows 63-66.