I would run lower tire pressures so that when it snows to give you more foot print. More TP will decrease your foot print and will provide contact point in the middle of the tire. I would run just enough to give you full contact- I would estimate somewhere between 30-35 PSI.
I was leaning towards this as I remember back in the drag days I would air down to get a fatter softer tire to grab onto the pavement. I am in no man's land thinking about snow tires and how grip in snow and ice/slush differs.
Do I want a larger foot print-or a smaller narrower footprint to cut through the muck down to the traction. At first, I was thinking that I wanted a hard stiff tire to cut through down to pavement. Then I started thinking the higher pressures made the tires too hard and there was a skating effect with the contact patches. Back to the start I thought a softer tire would grab more easily but snow and ice makes it more buoyant skimming over the snow and slush...ugh.
at this point I think about rally cars and they have narrow/thin tires with high pressures to firm up the sidewall and cut through the dirt and mud to reduce hydroplaning effect and get traction rather than having a big wide tire floating over the road.
Who knows-long story short, I am trying 37F/35 rear and may go down to 35/33 and see how that does.
As a side note-35/33 rides so much better