I bet it's a blended thing, multiple models.
This is not the time for Open Snow IMO. (Open Snow is bullish on the Cats right now. FYI)
If I am on the edge of my seat (and I am right now), I'm watching the point forecasts for the mountains, and reading the NWS ALY forecast discussion, that is updated at 4pm and 4am every day.
I like NWS ALY best, as a proxy for all the others. It spans from Gore/McCauley down to the Cats and you get a good idea of the spread so to speak. BTV is certainly useful for Northern VT, but you can almost assume NoVT any way. If it is snowing or a mix at Killington, the northern spine is likely good to go. NWS ALY is more about the battle zone dynamics vs VT. IMO.