For me, this was very hard to measure for some reason. I cleaned off the table last night, but my measurements still differed between 3.75" and 4.25" (a .50" range). I'm thinking that I did not do a great job cleaning off all the water residue, which then allowed some ice to form in certain areas. This perhaps caused the snow to begin accumulating on these icy patches first, therefore giving those sections a "head start" of sorts.
Anyway, I'm sticking with 3.75" lol.