The best skiing and riding conditions exist at and below tree line in sheltered locations. This is also where the January 17th Surface Hoar layer loiters.
Weather Forecast
Today starts with some clouds and light flurries; proceeded by sunshine as the high-pressure returns, pushing any precipitation south of Rogers Pass. The alpine may reach -14 and winds will be light. The clearing trend continues tonight; and the sun will be back tomorrow, before some snow begins to fall on Friday.
Snowpack Summary
A dusting of new snow covers old hard slabs, and wind scoured surfaces in the ALP and exposed areas of TL. These hard slabs are from Saturday's wind event; strong N-NE winds reverse loaded any available snow onto solar aspects, over a thin sun crust. The Jan 17th PWL is buried approximately 50-70cm at TL and below.
Avalanche Summary
On Saturday there was a natural cycle triggered by strong N-NE winds. Since the weekend we have only seen sporadic small wind slabs triggered by skiers up to size 1.5 in the alpine. There have been no reports of new avalanches on the Jan17th PWL in over a week.
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.
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.