Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1.5–2.5
New snow and wind is the recipe for wind slab avalanches and we have all the ingredients. We have an abundance of new snow coming in combined with moderate winds out of the west and southwest and wind slabs will build overnight and on Friday.
Lee features below ridges and highpoints will be places where triggering wind slab avalanches will be more likely. Wind speeds will be sufficient to crossload slopes as blowing snow wraps cross slope around features. Be cautious with your terrain choice and remember wind slabs are most sensitive to triggering when they are fresh.
Avoid the big pillows of wind drifted snow in start zones. Any time you see cracking in recent wind deposited snow or recent avalanches, recognize these as signs of unstable snow.
Use carefull evaluation in areas of sparse trees, clearings, and sections of dead forests. Open areas 'below treeline' can get enough blowing snow to create wind slabs.
Archive Photo: Jim W
Example of a small wind slab avalanche. Note the surface texture of the wind effected snow above the crown fracture. Ripply or pillowy surfaces are good indicators of wind loading.