A few other of the scenery taken at the same time.
The reason for the road being closed is not, as you might surmise, the depth of the snow pack. At that time it was just a few meters and not deeper than 10m anywhere, well within the capacity of modern snow-clearing equipment. The problem is the residual snow in the mountainous terrain surrounding the road as this snow pack easily creates avalanches.
First, a fisheyed view of the road. As I then set up the tripod for the image shown in the opening post, I heard the characteristic massive rumble of a big avalanche nearby. I had the old Nikkor 180-600 mm f/8 on the D3 and swung the lens over to capture the avalanche just as it came to a standstill a few seconds later. Doesn't look dangerous until you realise there is no indication of scale and in fact, the biggest blocks of snow in this picture were the size of a city bus.... Not something you wanted to hit the road whilst driving, that's for sure.
