With a problematic persistent layer, it's critical to stay disciplined and choose only well-supported, low-consequence lines.
A moderate danger rating means that large human-triggered avalanches are possible in isolated areas.
Localized wind slabs have likely formed in open terrain and near ridge tops due to moderate-gusty winds. Watch for newly formed and reactive small slabs as you transition into wind-affected terrain. Slabs in motion may step down to deeper weak layers, resulting in large avalanches.
Triggering persistent slabs avalanches will remain possible as the mid-December widespread weak layer is down 40 to 50 cm. Use extra caution where the snowpack varies from thick to thin, near rock outcrops and convexities. Larger-than-expected avalanches are possible due to the presence of a deeper weak layer.
Few natural occurrences were reported since Wednesday. Earlier this week, a large rider-triggered avalanche (size 2) was reported near Sun Peaks. The avalanche released from a persistent weak layer on a thin-thick steep roll.
Please continue to share any observations or photos on the Mountain Information Network.
Between 15-20 cm of light snow is now overlying the recent dense storm snow. New snow has been redistributed to northerly aspects at higher elevations. Fresh soft slabs may not bond well to previous surfaces such as hard wind-pressed snow.
The mid-December widespread weak layer of sugary faceted grains and/or small surface hoar is found down 40-50 cm. This layer was responsible for numerous large natural and human-triggered avalanches since Dec 27 in the neighboring region of Columbia. At lower elevations, a significant rain crust can be found down 40-50 cm. The November weak layer lies 90 to 140 cm below the surface. There is still a potential for smaller avalanches to step down to this deeper layer.
The majority of the snowpack is faceted, with roughly 140 cm found at treeline and less below treeline.
Periods of snow will persist overnight as the coastal system weakens. An upper ridge will be bringing widespread subsidence late Sunday and fair weather for the weekdays.
Saturday night
Light snow 2-5 cm, northwesterly ridge winds up to 30 km/h, treeline temperatures -3° C. Freezing level around 750 m.
Sunday
Mainly cloudy, isolated flurries, northwesterly ridge winds up to 20 km/h, treeline temperatures -3° C. Freezing level around 750 m.
Monday
Mainly sunny, no precipitation, southwesterly ridge winds at 20 km/, treeline temperatures around -8 °C. Freezing level at valley bottom.
Tuesday
Mainly sunny, no precipitation, southwesterly ridge winds at 20 km/, treeline temperatures around -10 °C.
More details can be found in the Mountain Weather Forecast.
