I lived in Bristol CT during that event. We had a lot of thunder and lightning later in the evening
I don't remember much about flakes size but it snowed at least two/hr for several hours with peak rates in the thunder snow reaching three/hr briefly. We picked up 18-19 inches from that and temps were right below 30F . That was man snow. We likely had around 2 inches melted equiv. With the six inch glacier beneath it we averaged just over 2 feet otg. Awesome storm!