Avalanche Forecast
Issued: Jan 6th, 2018 6:28PM
The alpine rating is Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Low - Due to the number of field observations
Weather Forecast
Occasional flurries with minor accumulations through the forecast period.SUNDAY: Cloudy with flurries / Moderate to strong west wind / Alpine temperature -4 MONDAY: Cloudy with isolated flurries, accumulation 3-5cm possible / Light southwest wind / Alpine temperature -2 TUESDAY: Flurries becoming snow overnight (5 - 10 cm possible) / Moderate southwest wind / Alpine temperature -4
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. See here for details in the MIN. 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. Expect 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
Strong to extreme south west winds picked up on Friday and redistributed snow into wind slabs on north through east aspects, as far down as tree line elevations. Some windward slopes have been scoured to ground. Temperatures have also warmed up significantly from the deep freeze, causing the storm snow from late December to settle and take on more slab-like properties at lower elevationsThe 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 proven to be reactive to human triggers. The lower snowpack is composed of mostly soft sugary faceted snow and early season crusts. Avalanche hazard is likely one step lower in areas east of the divide due to shallower snowpacks and the mid-December layer being less prominent.See here for a recent forecaster blog for a summary of the tricky conditions in the snowpack and strategies on how to work around a persistent slab problem.
Problems
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 7th, 2018 2:00PM