I'm a fairly dedicated all-year commuter.
I rather lose a few known minutes due to poorer roll than losing unknown time to a fall.
So I use winter tires with high stud counts these days. 200-300 range.
PSI don't change traction on ice or hardpack much for me.



What'll happen a few days each season though is that we get thick layers of fairly thick, soft snow.
It's not only traction, it's more about tracking.


That happens, I'll either not ride those days, or if caught out, will lower the pressure until I begin to feel the rim bottoming out, add a few strokes of the pump, pray not to pinch flat and ride.


As this happens along the road I don't have an accurate idea of pressure, but at a guesstimate it's below 2 Bar. Maybe 1.2-1.5.