A multiple regression analysis has been performed of the average annual number of avalanches and terrain factors. Observations were made at 36 paths at Rogers Pass over a period of 9 years. The average slope inclination measured from the starting point to the beginning of the run-out zone and exposure to wind proved to be the most significant variables. Slope angle at the starting point, variations over the track, and roughness of the ground surface were of secondary significance and their influence varied strongly from site to site. The analysis confirmed that avalanches need either a steep slope or a snow drift to start and a mimimum inclination of track to maintain their motion.