Seek out sheltered terrain and be suspicious of wind affected snow, like hard windslabs, cornices and cross-loaded slopes. Thin rocky areas will remain a concern in this complex snowpack.
Recent winds have hammered the surface at wind-exposed elevations. Wind slabs may be found unusually low on slopes due to recent strong winds and on all aspects due to changes in wind direction.
Cornices have seen significant growth recently. Give them a wide berth whether travelling on or below ridgelines. Cornices can be dangerous on their own and they can also act as large triggers to deep slab avalanches on slopes below.
Weak, sugary crystals at the bottom of the snowpack have produced large avalanches recently. These avalanches are most likely to be triggered by large loads such as cornice falls. However, in shallow snowpack areas they can also be triggered by the weight of a person and could propagate out to deeper snow resulting in large, destructive avalanches.
Our field team continues to observe numerous natural wind slab and cornice triggered avalanches up to size 2.
Last week, several large deep persistent slab avalanches were reported in the alpine, including a natural size 3 near Kispiox, a cornice-triggered size 2.5 at Hudson Bay and several explosive controlled size 2-3 near Ningunsaw.
Extensive wind effect from all directions characterizes the snow surface at upper elevations. Exposed windward aspects have been scoured, pillows of deep snow and wind slabs may be found sitting unusually low down in start zones and lees. Cornices are large and can be found on a number of aspects from persistent variable winds.
In sheltered areas, 40-50 cm of recent snow may be sitting over a layer of small facets and cold snow that feels upside down
Several other crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack, but have not shown any avalanche activity or tests results yet.
The lower snowpack consists of weak, basal facets which may become active with any rapid change or shock to the snowpack, such as heavy loading or dramatic warming. Snowpack depths range from 60 to 280 cm at treeline.
Saturday night
Possible flurries. Moderate easterly wind. Alpine low -15 ºC.
Sunday
Mostly sunny. Moderate easterly wind. Inversion up to -10 ºC in the alpine .
Monday
Mix of sun and cloud. Moderate southeasterly wind. Inversion in the morning. Alpine high -10 ºC.
Tuesday
Mix of sun and cloud. Possible flurries. Variable moderate wind. Alpine high -17 ºC.
More details can be found in the Mountain Weather Forecast.
