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September 2021 Issue
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A short little guide to the 7 types of avalanches

Get to know weather history and snowpack in local areas to identify these common types of avalanche hazards.

Storm slab: Large new layer of fresh snow, hasn’t yet bonded with previous snow surface.

Wind slab: Stiff layer deposited from wind loading, often on leeward slopes.

Wet slab: Thick slab that loses its bond with a previous layer due to warming.

Persistent slab: A weak layer buried 30-100cm below snowpacK.

Deep slab: A weak layer buried ,ore than 100cm. Harder to trigger but higher consequence.

Loose dry or wet: Surface level trigger and accumulate as they fall, also called point releases or sluffing. Most common in steep terrain.

Cornices: A build-up of snow off a peak, ridge, or ledge that can drop at any time.

Angle: Most avalanches happen on slopes 30° to 45°.

Skills: Take an avalanche safety course and check local forecasts frequently. Get to know the snowpack throughout the season, not just the day you’re venturing out. Check the avalanche advisory at