Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Stubborn wind slabs may lurk around ridges and in lee terrain. Check for wind-loaded pockets below ridgelines and in cross-loaded features.
Lingering wind slabs and persistent slabs remain possible to trigger.
Stubborn wind slabs may lurk around ridges and in lee terrain. Check for wind-loaded pockets below ridgelines and in cross-loaded features.
Facets in the mid and lower snowpack are most likely to be triggered in steep, rocky, wind-affected areas where the snowpack transitions from deep to shallow areas.
Over the past few days, there has been evidence of large cornice falls triggering wind slabs up to size 2. Whumpfing and shooting cracks (clear signs of instability) were also described in this recent MIN post.
A snowmobiler triggered a persistent slab avalanche last Sunday on the east side of White Pass. (MIN post here.) The avalanche failed on facets near the ground.
While it's outside the forecast area, this great MIN from Whitehorse describes conditions there.
Strong winds left behind stubborn wind slabs and hard, wind-affected surfaces. Some good riding and soft powder may still be found in isolated wind-sheltered locations at lower elevations.
Prolonged cold temperatures this winter resulted in a very weak, faceted mid to lower snowpack. Normally, thick and stiff wind-hardened layers would lower the likelihood of triggering these facets, but these layers are lacking their usual strength. Thick to thin upper treeline or lower alpine features are the most likely place to trigger deep weak layers in the mid and lower snowpack.
Saturday Night
Clear skies. 10 km/h north ridgetop wind. Treeline temperature -14 °C.
Sunday
Mostly sunny. 10 km/h northwest ridgetop wind. Treeline temperature -15 °C.
Monday
Mix of sun and clouds. 10 km/h southwest ridgetop wind. Treeline temperature -13 °C.
Tuesday
Mostly cloudy. 0 to 2 cm of snow. 20 km/h southeast ridgetop wind. Treeline temperature -10 °C.
More details can be found in the Mountain Weather Forecast.