Friction can help keep a slab of snow from sliding downslope. Samuel Colbeck of the Cold Regions Research and Engineering Laboratory has been researching what happens where frozen water molecules come together. Colbeck's research has changed the way people look at the snowpack when trying to predict avalanche conditions. Interestingly enough, Colbeck also sees other ways humans might be causing an increase in the number and severity of avalanches. Increased development and pollution in mountain regions can destroy trees, decreasing the natural buffers to avalanches.
Friction actually helps skis move over the snow.
It's not just the wax that makes skis go so fast. Skis move because they slide on a thin film of liquid water formed by the friction of the skis rubbing against the snow. Each ski generates about as much heat as three 100-watt lightbulbs as the skier zips down the hill. To understand more about friction, look at the Physics Explorer Mechanics activity Newton's Laws. Dry slab avalanches most often travel at speeds of 65 to 80 miles per hour.