| Trigger | Water from warming, sun, or rain |
| Motion | Slower but dense and destructive |
| Timing | Daytime warming, spring melt |
| Signs | Roller balls, pinwheels, sinking, slushy snow |
A wet avalanche occurs when liquid water from melting (warm temperatures, strong sun) or rain saturates and weakens the snowpack, causing wet, heavy snow to release. Wet avalanches move slower than dry slides but are dense and destructive, and their timing is often predictable — rising with daytime warming and spring melt — making timing and observation key to avoiding them.
This is general educational information, not avalanche training.
Timing is everything
A warm-snow avalanche tied to snowpack melt — travel on firm snow early; the same melt-freeze makes corn snow.
Frequently asked questions
What is a wet avalanche?
A wet avalanche is one that occurs when the snowpack becomes wet from melting or rain, so liquid water weakens the bonds between snow grains and saturated snow slides. They can be loose (point-release) or slab in form, but all involve wet, heavy snow and are common during warming and the spring melt cycle.
What are the warning signs of wet avalanche danger?
Signs include snow becoming slushy and unsupportable, your skis or feet sinking deeply, roller balls and pinwheels rolling down slopes, water running in the snow, and recent rapid warming, intense sun, or rain. As the snow surface loses cohesion and you sink in, wet-slide danger is rising.
How do you avoid wet avalanches?
Largely through timing: travel on firm, frozen snow early in the day and get off and out from under steep slopes before the snow softens significantly in the afternoon sun. Heed the avalanche forecast for wet-avalanche problems, and avoid steep slopes during or right after major warm-ups or rain.
Sources
- Wet avalanches — Avalanche.org
- Wet snow instability — American Avalanche Association