I commute (9 miles) and last winter, with the help of studded Suomi (Nokian) 26x 1.9s I returned to snow riding after many (many) years. My main goal was being able to ride on icy side streets, something I had never had success with. The studded tires were a tremendous success and allowed me to easily (and smugly) ascend icy uphills next to cars struggling to gain purchase on the ice.

But I found 3 inches of loose snow to be the practical limit for me. In snow that deep my forward progress was pretty much walking speed. Now, for fun and enjoyment I'm not sure what the limit is, and I remember riding fenderless in snow 5 or six inches in places back in my 20s, but that wasn't commuting.

My "snow bike" is my previous main commuter, a 1997 Nishiki Blazer. Here are some snow rides: