Make continuous observations of the depth and reactivity of new snow as it stacks up. Be ready to dial back your terrain selection when you see signs of instability.
New wind slabs will begin to form as light to moderate snowfall combines with strong south winds. Weak snow grains and a hard crust in the upper snowpack suggests there may be a possibility for some slabs to fracture deeper than expected.
A skier accidentally triggered an small (size 1) wind slab on Friday in the Beaufort Range. Check out this MIN for the details. It is a good reminder that a problematic layer exists below some wind slab formations that has kept them surprisingly sensitive to triggering. Reports have otherwise been quiet.
Looking forward, concerns shift to new snow accumulations under elevated winds for Wednesday.
10-20 cm of new snow should accumulate at higher elevations by end of day Wednesday under strong southeast winds. It will add to a rapidly settling 5-10 cm of snow from Sunday.
The new and recent snow is burying a variety of surfaces, including crust on sun-exposed slopes, old wind slabs, and up to 20 cm of old, soft, faceted snow in sheltered north-facing terrain. It's uncertain as yet whether new wind slabs may be capable of fracturing deeper than expected where they overlie this faceted snow.
The mid and lower pack contains deteriorating old crusts and storm layers that are now for the most part dense, homogenous, and moist.
Below treeline, most areas are below the threshold for forming avalanches.
Tuesday night
Cloudy with continuing wet flurries bringing 5 - 10 cm of new snow to the alpine, light rain below about 1400 m. 15 - 30 km/h south alpine wind. Treeline temperature +1 °C with freezing level staying near 1500 m.
Wednesday
Cloudy with continuing flurries bringing 5 - 10 cm of new snow to higher elevations, light rain below about 1200 m. 20 - 30 km/h southeast alpine wind. increasing. Treeline temperature 0 °C with freezing level to 1300 m.
Thursday
Cloudy with easing isolated flurries and 36-hour snow totals of up to 30 cm in the alpine, tapering rapidly at lower elevations. 15 - 20 km/h southeast alpine wind. Treeline temperature 0 °C with freezing level around 1400 m.
Friday
Mainly cloudy with scattered light rain or wet flurries in the alpine. 20-30 km/h southwest alpine winds. Treeline temperature +2 with freezing level rising to 1700 m.
More details can be found in the Mountain Weather Forecast.
