With new snow and warmer temperatures, the snowpack is entering a time of change. Expect buried layers to become more reactive in the coming days.
Weather Forecast
Today expect cloudy with sunny periods and isolated flurries amounting to no more than a couple cms. Freezing level will rise to 1500m, giving us an alpine high of -4 deg C. Wind will be from the West in the 20-40km/h range. A series of pacific systems will bring precip though the week with up to 30cm of accumulated snow forecast by Wednesday
Snowpack Summary
We received 5cm of new snow overnight with moderate alpine winds which burying a thin suncrust on solar asps. Dec 27th surface hoar is buried down 30cm and starting to produce results in tests. The Dec 15th surface hoar is still the main layer of concern, buried 60 deep which is producing whumphing, cracking and small slides around tree-line.
Avalanche Summary
No new avalanches were observed yesterday in the highway corridor. A field team on Macdonald West Shoulder was able to ski cut 2 small slabs on the December 15 Surface Hoar Layer in steep, unsupported terrain. Report of a sz 1.5 skier triggered avalanche(30 cm deep) on the Balu Headwall suggests the Dec 27th surface hoar is becoming reactive.
Confidence
Track of incoming weather systems is uncertain
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.