A persistent weak layer of surface hoar has been reactive to human-triggering in recent days. The safest way to manage this problem is through conservative terrain choices.
Wind slabs may remain sensitive to rider traffic at treeline and above. Avoid wind-loaded areas and watch for fresh, reactive slabs forming throughout the day.
Buried surface hoar remains rider triggerable. This layer is a concern in areas where a significant crust is not found above it.
A natural avalanche cycle occurred in the past few days. Several rider triggered slab avalanches have also been reported.
Check out this MIN from Powder King, detailing a skier-triggered persistent slab. This MIN shows several avalanches that occurred in Torpy on Friday. We suspect that these avalanches ran on one of the surface hoar layers in the top meter of the snowpack.
Looking forward to Monday, reactivity is expected to persist with wind and warm temperatures.
Recent storm snow has been redistributed into wind slab near ridge crests by southerly winds. Below treeline a new crust is on or near the surface.
The mid pack contains several layers of note; a layer of surface hoar and a crust down 20 to 30 cm , a significant crust from the early December rain event down around 50 cm and a layer of surface hoar down 60 to 100 cm.
Snowpack depth throughout this region is highly variable and as a result the depths of the above mentioned layers are approximate and could be different than what you find in your riding area.
Sunday Night
Clear periods with no new snow. South alpine wind, 30 to 60 km/h. Treeline temperature -6°C.
Monday
Cloudy with sunny periods, no new snow. South alpine wind, 30 to 70 km/h. Treeline temperature reach a high of -1 °C.
Tuesday
Cloudy with snowfall, 1 to 10 cm of accumulation. South alpine wind, 40 to 100 km/h. Treeline temperature 0 °C.
Wednesday
Mainly cloudy with isolated flurries. South alpine wind, 30 to 60 km/h. Treeline temperature -1 °C.
More details can be found in the Mountain Weather Forecast.
