Which of the following is NOT listed as a factor influencing avalanche runout?

• A. Mass
• B. Transitions
• C. Drop
• D. Wind

Answer: (D)

Understanding runout distance means looking at how the moving snow mass interacts with terrain after release. The mass of the avalanche carries momentum, so a heavier slide tends to travel farther on the same slope. Terrain transitions—changes in slope angle or geometry—shape where energy is dissipated, which can either slow the flow or let it keep going. A drop or sudden change in elevation alters the path and energy balance of the moving snow, affecting how far it can travel. Wind, while key to snowpack stability and whether a slide will start, doesn’t directly determine how far an avalanche travels once it’s moving, so it isn’t listed as a factor influencing runout.