The high temperature reached 90° in many inland locations in Southern New England on Independence Day. The dew point stayed in the low 70s, and that had it feeling like 95-100° in many spots away from the coast in the middle of the afternoon. It will be warm and muggy Thursday night. Skies will be hazy, with the temperature gradually falling through the 80s into the mid 70s inland by dawn. It will be closer to 70° near the coast where there may be a bit of fog.
Friday looks like another hot one in the Northeast. You can expect hazy sunshine with highs in the low to mid 90s inland, and 80s near the coast thanks to a southwesterly breeze. The hot, humid weather sticks around for the weekend, too. Friday night looks uncomfortably warm and muggy, the low temperature in the cities may not get below 75°. Saturday afternoon will feature sun, clouds, and highs in the low to mid 90s inland. The coast will be in the 80s. It should be a great beach day.
The weather will stay hot and humid on Sunday. It will likely be the fourth day of an inland heat wave as high reach 90° again. A front may get close enough to trigger a late-afternoon thunderstorm in interior Southern New England. Monday is shaping up to be unsettled, with a thunderstorm threat as a disturbance moves through. It will be very warm and muggy, but likely not as hot as the weekend.