Without repeating what others have said I will add April 4, 1987 in SE Ohio to the list. We had 24" on the ground of the wettest heaviest snow I have ever seen accumulate. It was 36° the entire time it snowed. The first 4 hours or so of snow during the daylight hours melted on contact, but once evening set in it started sticking to everything. This was basically a 24 hour snowfall so the rates were fairly impressive. It melted only a couple of days later, but I will never forget that one.