Snow is in the forecast!With new snow and moderate temps, the snowpack is entering a time of change. Expect buried layers to become more reactive in the coming days.
Weather Forecast
Expect cloudy skies with periods of light snow flurries. The alpine high will be -6 with freezing levels reaching 1300m. Winds will be from the south in the 20km/hr range. Several waves of precipitation are expected for the next week delivering a consistent 5-10cm of snow daily.
Snowpack Summary
10cm of new snow in the past 48hrs with moderate alpine winds has buried a thin crust on solar aspects. Dec 27th surface hoar is buried 30-40cm and starting to produce results in tests. The Dec 15th surface hoar is still the main layer of concern, buried 60cm deep which is producing whumphing, cracking and small avalanches at and below tree line.
Avalanche Summary
Numerous sz 1.5-2.5 observed yesterday along the highway corridor from steep terrain. Test results from the past few days show that the Dec 27th surface hoar layer is becoming reactive, producing moderate sudden planar fractures in some profiles.
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.