TT uses True SLR for the Icon which I read was an alternate to Kuch. It is not necessarily 10-1 and, in this case, does not match up with the qpf map if it were 10-1. Here is the Icon 10-1 on Pivotal. Much higher than TT with the point being gross differences between model sites snow maps is always a cause for confusion. WB is almost always higher than the rest for true snow situations.