Today this storm would have been called a hurricane. It was a cat 3 and one of the 5 major hurricanes to hit New England.
It hit Long Island, NY, moved across the island and hit land again at Saybrook CT. There was an 11 ft. storm surge that hit Providence, RI was hardest hit. In the book "Ships and shipmasters of old Providence there is a copy of a lithograph and this caption. During the Great Gale o September 23, 1815, ships were tossed about in Market Square; 35 sailboats were blown ashore; 500 buildings were destroyed: and the sloop-of-war Ganges poked her bowsprit into the offices of the Washington Insurance Company. A damage of $1,000,000 was sustained in Providence.
The storm continued it's path up thru Boston and then hit parts of Maine. Well were flooded with sea water, making fresh water on the coast towns hard to come by and when they acquired some they paid a hefty price. The sea spray also killed the leaves on the trees. I saw this effect while traveling I10 right after Katrina hit. The trees looked brown where the salt water had hit them. Pine and evergreens were brown on one side and green on the back side to the wind. In 1815 after the great gale they found they had to harvest their root plants and dry them off. If they didn't the vegetables rotted in the ground. The Indian corn was wiped out because it had not ripened before the storm and there was no way to dry out the plants. Some locations, where the corn had started to ripen, managed to harvest some of their crop.