Wind is driving the avalanche danger on Monday. I would expect to find touchy wind slabs on lee features below ridgetops and good skiing in sheltered terrain.
Confidence
Moderate - Forecast snowfall amounts are uncertain
Weather Forecast
MONDAY: Snow beginning Sunday evening and is expected to accumulate to 10-20 cm by Monday afternoon. Moderate southwesterly ridgetop winds, and temperatures around -12.TUESDAY: Mix of sun and cloud, moderate northwesterly ridgetop winds, and temperatures around -18.WEDNESDAY: Mostly sunny with cloudy periods, light northwesterly ridgetop winds, and temperatures around -20.
Avalanche Summary
On Saturday, numerous size 1 human triggered wind slabs were reported on northerly aspects. I expect human triggered wind slab activity to increase on Monday with the forecast new snow and wind.
Snowpack Summary
Forecast 10-20 cm of new snow by Monday afternoon and moderate southwest winds are expected to create fresh wind slabs on lee features at treeline and above. Recent snow has also covered old, thicker wind and hard slabs from previous wind events. Persistent weak layers in the mid-pack are giving variable results in snowpack tests, but are generally most touchy in shallow snowpack areas. Recent snowpack tests gave moderate to hard but resistant results on two different layers of facets and/or buried surface hoar in the top metre. The lower snowpack seems to be well bonded, but features a crust/facet deep persistent weakness near the ground, which remains a concern in shallow rocky snowpack areas.
Problems
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.