This stuffy, steamy night will be illuminated by some moonshine through some patchy high feathery cloudiness. Temperatures will not drop below the lower to middle 70s in most locations. Low cloudiness and areas of fog are most likely over much of Cape Cod which will burn off tomorrow morning. A weakening frontal boundary spiked a few storms across northern New England late this afternoon and early evening. This boundary will lose its identity as it flounders into northern MA late tonight and early tomorrow. It may provide a focus axis for some showers and storms to pop up tomorrow afternoon but atmospheric parameters fall short of generating any widespread action and certainly nothing severe. The main feature would be tropical downpours and some cloud to ground lightning bolts. Temperatures will nudge and slightly exceed 90 degrees again making it another official heat wave for many locales away from the ocean. Contrary to today, the breeze will become onshore at east-facing beaches resulting in max temperatures about 6-8 degrees below today’s 91-95. Boston’s 3:37pm high of 92 will not be matched tomorrow due to an anticipated east-southeasterly breeze at 6-12 mph. Low cloudiness may become more widespread across the region tomorrow night with lows in the 70-75 range again. Some burnoff will reveal varying amounts of higher clouds with sunshine penetrating through at times on Sunday. Ahead of an approaching stronger frontal boundary from NY, a freshening southerly wind to 12-25 mph is probable thereby keeping south-facing coastal areas cooler in the upper 70s to lower 80s while the rest of the area is also a bit cooler on Sunday with highs of 86-90. There may be a few renegade showers and storms popping off Sunday afternoon but the main event happens after midnight Sunday when a more solid swath of showers and storms shifts eastward across New England. Presently, the timing places the batch rumbling through the Boston area from 4-8am Monday. This axis of action will shift southeastward across Cape Cod through the morning then offshore by midday.
Looking ahead, following the frontal passage Monday morning, the air will become less humid during the day via a nice west-northwesterly breeze. It will be more comfortable in the afternoon with some sunshine sending temperatures back to the upper 80s. This more pleasant air mass will linger through midweek as a bubble of high pressure transits over the region. The next weather maker will create more cloudiness late Wednesday with some showers and possible storms here on Thursday. After that, a deepening trough of low pressure digging in from the Midwest will produce a surface wave of low pressure. This system could provide a decent round of rain here later next Friday into Saturday morning. That is certainly not etched in stone just yet.
In the meantime, you can keep tabs on any action in the tropics by logging on to the National Hurricane Center. Presently, Tropical Storm Ernesto is centered a bit over 300 miles south-southeast of San Juan Puerto Rico with maximum sustained winds of 50 mph. Conditions may become more favorable for strengthening later this weekend as the storm moves rather swiftly westward towards the Yucatan Peninsula. Additionally, a well-defined low pressure area and tropical wave is located about 230 miles west of the Cape Verde Islands. This system has the potential to develop into Tropical Storm Florence within 48 hours.
Joe Joyce delivers his AccuWeather Forecasts tomorrow and I shall return later Sunday.
Have a happy and safe weekend.