Expect to continue to see persistent slab avalanche activity as the snow sitting above the persistent weak layer further settles and consolidates with forecast warmer temperatures. Adopt a conservative approach in the coming days.
Summary
Confidence
Moderate - Due to the number of field observations
Weather Forecast
FRIDAY: Cloudy with isolated flurries / Light west wind / Alpine temperature 2 SATURDAY: Cloudy with isolated flurries / Light to moderate west wind / Alpine temperature -3 SUNDAY: Cloudy with isolated flurries / Light to moderate west wind / Alpine temperature -5
Avalanche Summary
Continued avalanche activity was observed in steep low elevation terrain (road cut banks) in the Elk Valley on Wednesday to size 1.5. These were triggering very easily. On Monday, a machine triggered Size 1.5 persistent slab avalanche was reported running on the mid December surface hoar layer, down 35 cm at that location (1700m). See the details
here in a Mountain Information Network (MIN) post. On Sunday a Size 2 persistent slab (stepping down to late November crust/facets) was intentionally triggered on an east aspect near 2000m in the south of the region. Expect to continue to see persistent avalanche activity continue as temperatures revert to a normal regime (warmer in the valleys and colder with elevation) and snow sitting above persistent weak layers settles more rapidly.
Snowpack Summary
Up to 45 cm of snow fell to end 2017. Since then, moderate to strong winds from a wide range of directions have redistributed that snow into wind slabs tree line and above. The main concern in the snowpack is a weak layer buried mid-December, which consists of a crust on solar aspects and feathery surface hoar in sheltered terrain at and below tree line. This layer has consistently shown to be reactive to human triggers. The lower snowpack is composed of mostly soft sugary faceted snow and a early season crusts.
mbender,
Avalanche Canada
