Climbing steep slopes on a snowmachine.

Credit: Flathead Avalanche Center

High marking is a popular activity performed by snowmachiners, where the operator rides as far up a steep slope as possible, then turns around and comes back downhill. Because optimum high marking is on steep, avalanche-prone slopes, many snowmobile avalanche accidents are associated with high marking. When high marking you can reduce your avalanche risk by: 1) High mark one at a time while your partners watch from a safe area well out of the potential runout zone, 2) High mark on days when the avalanche danger is lower and the avalanche problems are smaller and/or easier to identify, 3) Start on smaller slopes with clean runouts free from trees, gullies, and other terrain traps to get a feel for the snow stability, 4) If your partner gets stuck on a steep slope while high marking, let them wrestle their sled free on their own so as not to expose more people to the slope, and 5) Be sure to wear your avalanche gear (beacon, shovel, probe, airbag) on your body so you will have it immediately available if you get separated from your sled in an avalanche. 

Don’t watch your partner high mark from below the slope.

An avalanche triggered by a snowmobile high marking. Credit: Gallatin Nationa Forest Avalanche Center