Be cautious of sluffing in steep terrain.
Weather Forecast
Isolated flurries will continue today with freezing level at valley bottom and light to moderate ridgetop winds., with The incoming storm will deposit the bulk of the snow tonight into Monday, with freezing levels rising to 1100m. Forecast amounts are 10 to 20 cm. Temperatures will cool off and snow precipitation is forecast for Tuesday.
Snowpack Summary
15 of low density HST from the last two days sits on the surface. Below that up to 80cm of snow has settled over surface hoar at lower elevations, mixed forms and variable wind slabs at higher elevations. This interface is failing sudden planar in snowpack tests. At the base of the snowpack 2 persistent weak layers are surrounded by mixed forms.
Avalanche Summary
We observed 6 natural avalanches yesterday morning along the highway corridor, running in the storm snow with low density HN and moderate winds. The avalanches were mostly size 2-2.5, and deposited snow at the beginning of the runnouts.
Confidence
Intensity of incoming weather systems is uncertain on Monday
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.