Avalanche snow pits can be an essential means to determine snow layer stability in the mountains. By digging a snow pit, one is able to see and test the layers. The information that is gathered can then be used to help make decisions on what terrain to ride.
What is an Avalanche Snow Pit?
An avalanche snow pit (often just called a snow pit) is a hole dug into the snowpack. It allows backcountry travelers, guides, and avalanche forecasters to study the layers of snow and assess avalanche risk.
What it’s used for
Snow doesn’t fall all at once—it builds up in layers over time. Some layers bond well. Others are weak and can fail and cause avalanches. A snow pit helps you:
- See how the snowpack is layered
- Identify weak layers (like facets or surface hoar)
- Test how easily layers might slide
- Make safer travel decisions in avalanche terrain
What it looks like
- Usually dug to the ground or at least 1–2 meters deep
- About arm-span wide so you can clearly see the layers
- Dug on a representative slope (similar elevation, aspect, and angle to where you plan to travel)
What people examine in a snow pit
- Snow layers – Different colors, grain sizes, and hardness
- Grain types – Rounded grains, facets, crusts, etc.
- Layer bonding – How well layers stick together
- Weak layers – The most important factor for avalanches
Common snow pit tests
- Compression Test (CT): How many taps it takes to cause a fracture
- Extended Column Test (ECT): Whether a crack spreads across the column
Important note
A snow pit gives localized information only. Conditions can change dramatically across a slope or even within a few meters, so pits should always be combined with:
- Avalanche forecasts
- Recent weather data
- Terrain management
- Conservative decision-making
