There is uncertainty with the distribution and reactivity of a recently buried weak layer of surface hoar. Until there is a better understanding of how reactive it is and where it can be found, it is best to make conservative terrain choices.
40-70 cm snow has accumulated over a weak layer of surface hoar. There is uncertainty with the distribution and reactivity of this layer. Until there is a better understanding of how reactive it is and where it can be found, it is best to make conservative terrain choices.
Friday Night: Flurries, accumulation 5-10 cm. Alpine temperature -4 C. Southwest wind 20-30 km/hr. Freezing level 500 m.
Saturday: Scattered flurries. Alpine temperature -3 C. Southwest wind 20-40 km/hr. Freezing level 600 m.
Sunday: Cloudy with sunny breaks. Alpine temperature -4 C. Southwest wind 10-20 km/hr. Freezing level 500 m.
Monday: Flurries. Alpine temperature -5 C. South wind 15-30 km/hr. Freezing level 500 m.
There were reports of a few natural size 1 storm slab avalanches in the Shames area on Thursday.
Natural storm slab avalanches to size 1.5 were observed around treeline on Wednesday and loose, dry snow was running from steep alpine features. Avalanche control work Wednesday and Thursday triggered numerous large (size 2) avalanches with explosives, crown depths ranged from 30-80 cm.
40-70 cm of snow has accumulated over a weak layer of surface hoar, old faceted surfaces, and/or a crust on south/southwest aspects in the alpine. Reports from the Shames area suggest the surface hoar layer is prevalent on all aspects at treeline elevations down to 800 m, and more likely on leeward and sheltered alpine areas. Check out this MIN report from sheltered terrain near Shames.
The lower snowpack is generally considered strong, as there has been very little to report in terms of recent avalanche activity or snowpack test results on deeper layers. Snowpack depths at treeline range from 100-200 cm and taper quickly at lower elevations.
