The good news...❄️ winter is back! ❄️
The bad news... storm snow may not bond well with the crust.
Dial back your terrain choices as storm snow accumulates this weekend.
Watch for reactivity in wind affected features. Although Saturday's storm totals will be small, slabs may slide easily on the crust below.
The likelihood of avalanches on buried weak layers is decreasing, but we are uncertain how quickly. High-consequence slopes should be approached with caution.
Natural avalanche cycles continued throughout this week with rain, warming, and sunshine weakening the upper snowpack. Wet loose and wet slab avalanches (on the facet layer 30-60 cm deep) were reported to size 2.5. Cooling on Thursday and Friday limited further activity.
Moving forward avalanche activity will become more likely as storm snow accumulates.
Up to 10 cm of storm snow is expected to accumulate over Saturday. This will fall over moist snow at low elevations, or over a crust at higher elevations and may not bond well.
A layer of facets (and small surface hoar in some areas) is buried 30-60 cm deep and a layer of facets on a crust is buried 80-100 cm deep. The cooling trend is expected to strengthen these layers, but we are uncertain how quickly this will happen.
Friday Night
Cloudy with no new snow expected. Light and variable winds. Freezing levels drop to around 1300 m.
Saturday
Cloudy with up to 10 cm of snow expected over the day. Freezing levels remain around 1500 m, with treeline temperatures around -2 °C. 10-30 km/hr easterly winds.
Sunday
By Sunday morning another 10-20 cm is possible. Freezing levels reach 1500 m again. Treeline temperatures around -2 °C. Southeast winds, 10-20 km/h.
Monday
A mix of sun and cloud with flurries is possible. Freezing levels reach 1500 m over the day. Treeline temperatures around -2 °C. Southeast winds 20-40 km/h.
More details can be found in the Mountain Weather Forecast.
