Avalanche danger will increase as new snow and wind form fresh and reactive wind slabs in lee terrain features at upper elevations.
Watch for fresh wind slabs forming in lee terrain features. Older wind slabs sitting over a crust may also remain reactive to human triggering on steep, convex and/or unsupported terrain features.
Friday night: Flurries starting, bringing up to 5 cm. Strong southwest wind. Freezing level valley bottom.
Saturday: Snowfall 5-10 cm. Strong SW wind. Treeline high around -3 °C.
Sunday: Snowfall 5-15 cm. Moderate to strong SW wind. Treeline high around -2 °C. Freezing level 1000 m.
Monday: Snowfall 5-10 cm. Moderate NW wind. Treeline high around -8 °C. Freezing level valley bottom.
No new reports of avalanche activity.
Earlier in the week, several reports from the south of the region indicated wind slabs were reactive naturally and to explosives, size 2-3. Some of these were failing down to the bedrock in extreme terrain features.
The snow surface is highly wind affected in exposed terrain and wind slabs are lingering in leeward features. On steep solar aspects and at lower elevations, a melt-freeze crust may be found on the surface. In sheltered areas at treeline and below, a layer of small surface hoar crystals has been reported in the south of the region.
A thin crust may be found under the last week's snow down 20-30 cm, which was the main sliding surface for the wind slab cycle last weekend. Another crust is found down around 70 cm but has not shown recent reactivity. The lower snowpack is generally strong and bonded, with one or multiple crusts near the ground. We suspect the lower snowpack could be weak in shallow, rocky, wind-affected slopes east of the divide.
