Triggering wind slab avalanches is possible in steep open terrain.
Expect to find increasingly deep and potentially reactive wind slabs as you gain elevation into the alpine. Danger is low in areas that have a solid crust on the surface.
TUESDAY NIGHT: Cloudy with light flurries, moderate wind from the west, alpine temperatures drop to -12 C.
WEDNESDAY: Scattered flurries with 5-10 cm of low density snow, moderate wind from the west, alpine high temperatures around -8 C.
THURSDAY: Cloudy with isolated flurries, light wind from the west, alpine high temperatures around -5 C.
FRIDAY: Mix of sun and cloud with storm approaching in the evening, light wind, alpine high temperatures around -5 C.
A large cornice fall was reported on Tuesday, and fragile cornices were also observed on Monday. A few small (size 1) wind slabs were triggered by riders on north aspects on Sunday. A widespread natural avalanche cycle on Friday night resulted in large (size 2-3) storm slab, wet slab, and wet loose avalanches. Reports suggest deeper weak layers were not involved in these avalanches.
With a crust capping the snowpack in most areas, the main concern is now small stubborn wind slabs above the crust.
Strong southwest winds have likely formed isolated wind slabs in the alpine and exposed treeline areas above 2100 m. Below this elevation, 5-10 cm of snow, also wind-affected, covers a solid melt-freeze crust that now caps the mid and lower snowpack. In many areas this capping crust may extend to mountaintops.
The bottom 10-20 cm of the snowpack consists of faceted snow and decomposing crusts. This basal layer has not been an active avalanche problem in the region since December and would likely require a sustained warming event before re-emerging as a concern.
