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Where Do Avalanches Happen?

Slope Angle

Slope angles on which avalanches occur tend to be those favoured by skiers, snowboarders, and snowmobilers.

Slope angle is the most significant characteristic of an avalanche slope. The vast majority of avalanches take place on slopes between 30° and 45°, which is about the steepness of a black run on a ski hill. It’s also the preferred terrain for many backcountry enthusiasts.

Avalanches can happen on less steep slopes between 25° and 30°, but they are not as common. On slopes steeper than 45°, snow usually slides away frequently, so slabs are less likely to form. Keep in mind that an avalanche that starts in steep terrain can run across a flat slope and even travel uphill.

Dig Deeper: Identifying Slope Angle +

Learning how to assess the steepness of a slope is a good skill to develop. One inexpensive tool that will show you the steepness of a slope is a clinometer (or inclinometer). There are smartphone apps that do this as well.

A clinometer
Nicole Matei