Avoid avalanche terrain as very dangerous conditions will persist.
The complex snowpack will be exposed to warming on sun-exposed slopes.
Three problematic persistent weak layers exist in the upper 170 cm of the snowpack. Recent snow is adding load to these layers, and large destructive avalanches are possible. Remote trigger and release on low-angle slopes is also likely.
Continued snow, combined with strong wind, have developed fresh reactive storm and wind slabs. Storm slabs in motion may step down to deeper layers, resulting in large avalanches.
A natural cycle with numerous very large persistent slab, storm slab, and wind slab avalanches up to size 4 were reported on Friday and Saturday throughout the region.
A surprisingly large avalanche was remotely triggered by a skier (size 2.5) on a south-east aspect at treeline, with noticeable step-down to deeper persistent weak layers on Friday.
Multiple climax avalanche events were reported in the neighboring region.
50 to 90 cm of recent storm snow overlies a complex snowpack. Strong westerly wind redistributed this snow farther downslope than usual.
Three persistent weak layers of concern are found in the upper 180 cm of the snowpack:
60 to 70+ cm down is a layer of surface hoar in sheltered areas, or a melt-freeze crust on sun-exposed slopes from mid-February.
90 to 120+ cm down is the early-February layer of surface hoar in wind-sheltered terrain and a crust on sun-exposed slopes.
110 to 140 cm down is the late-January layer of surface hoar and facets over a melt-freeze crust.
All of these persistent layers have continued to produce large avalanches.
The remainder of the snowpack below is well consolidated.
Saturday Night
Clear skies. 30 km/h west ridgetop wind. Treeline temperature -7 °C.
Sunday
Sunny. 40 km/h west ridgetop wind. Treeline temperature -5 °C.
Monday
Mix of sun and clouds. 1 cm of snow. 40 km/h west ridgetop wind. Treeline temperature -1 °C.
Tuesday
Mostly cloudy. 4 to 15 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature -2 °C.
More details can be found in the Mountain Weather Forecast.
