SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/ski-avalanche-slope-angle

Most slab avalanches start on slopes of what steepness?

30 to 50 degrees.

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  1. 5 to 15 degrees
  2. 30 to 50 degrees ✔
  3. 60 to 80 degrees

Why: A Swiss dataset of over 1,000 avalanches found that 96 percent released on slopes between 30 and 50 degrees. Steeper slopes tend to shed small loose snow instead.

Huh, didn't know that: Avalanche.org says avalanches starting on slopes under 30 degrees are rare because the incline is so flat.

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As I grow, I come closer to the ground. What am I? An icicle.
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References

Answer: 30 to 50 degrees. A Swiss dataset of over 1,000 avalanches found that 96 percent released on slopes between 30 and 50 degrees. Steeper slopes tend to shed small loose snow instead.

  1. Avalanche.org: Slope angle avalanche.org/avalanche-encyclopedia/terrain/slope-angle
    between 30° and 50°
    Checked 2026-10-10.

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