In my mind, the atmosphere is fluid. So I look at all of the terrain generated snowfall like rocks in a river. The inversion is the depth of the water, in the river scenario, and that’s what matters IMO. The inversion height can explain most mountain snows.
In this case, it was a light flow overall but with a 900-850mb inversion. Maybe some acceleration of the flow over and down the lee side, only for speed convergence to occur as the flow slows down slightly on the lee side. The air was being squeezed out around the peaks. A void was created downstream of the peaks, air rushed in to fill the void and where it collided (convergence) when wrapping around a peak, it created a narrow band of snow on the backside of the higher peaks.
Some turbulence and convergence (atmosphere is fluid, Iike water over rocks), brought localized narrow WNW to ESE bands of snow over 12-24 hours.