Forecast discussion: We had partly to mostly sunny skies over Boston for most of Monday. However, thanks to the sunshine, this helped create pockets of showers and isolated periods of heavy rain. In fact, a few thunderstorms passed south of Boston during the mid-afternoon. As the sun sets, we will lose the risk for more shower activity, but the temperature being close to the dewpoint will create patchy fog this evening.
As we move through the middle of the week, a cold front now passing over Buffalo, NY will make its way into Southern New England by Tuesday night. This front may help trigger some isolated showers or thunderstorms during the afternoon, especially in the northern sections of the state. The best chance for isolated to scattered precipitation will be Wednesday, as the front lingers right over Rhode Island and eastern Massachusetts.
The front will be slower than forecast to move offshore. So, I have to add the risk of some an afternoon shower or thunderstorm for Thursday. By then, a strong high pressure system now over Ontario, Canada will move over the Great Lakes by Thursday afternoon. This high will then slowly move into the Mid-Atlantic, giving us sunny weather for the entire weekend. Winds will eventually come back from the southwest, and this will help raise our high temperatures into the lower 80’s for Saturday and Sunday. But, the weather pattern shows no hot spells arriving in Southern New England for the next seven days.
Meanwhile, this is the first time in 22 years that the first named tropical systems reached hurricane status. Hurricane Bertha was centered at 29.4N 76.3W, or about 560 miles west-southwest of Bermuda, as of 5 p.m. EDT. It is just a minimum hurricane with maximum sustained winds at 75 mph, and is moving north at 18 mph.
The forecast is for Bertha to become a Tropical Storm within 36 hours, as it begins to move into cooler waters. It will become an extratropical system within 72 hours. The track has the system moving towards the northeast and away from the east coast. However, Southern New England will begin to see rising seas outside of Narragansett Bay by Wednesday night, along with an increased chance for moderate rip currents at the beaches.
72 hour forecast:
Tonight: Scattered showers until 9 before skies become partly cloudy. We will see a low of 66.
Tuesday: Mostly sunny with the slight chance for some late afternoon showers/thunderstorms. We will see a high of 85 with south-southeast winds of 9-12 mph.
Tuesday night: Mostly cloudy with possible showers and a low of 67. Winds will shift to the west-northwest at 5-8 mph.
Wednesday: Partly sunny with the chance for showers/thunderstorms, starting in the late morning. We will have a high of 81.
Wednesday night: Showers end during the early morning. We will see a low of 63.
Thursday: Partly to mostly sunny with an isolated afternoon shower or thunderstorm. We will see a high of 79.
Thursday night: Partly cloudy with a low of 63.
Friday: Mostly sunny. Highs 76-79, lows 61-64.
Saturday: Mostly sunny. Highs 79-82, lows 62-65.
Sunday: Mostly sunny. Highs 81-84, lows 63-66.
Monday: Mostly sunny. Highs 81-84, lows 63-66.