A reactive persistent weak layer remains a primary concern for the region.
Start with simple terrain and gather information before committing to bigger features.
5 to 10 cm of new snow is forecast for Sunday, combined with moderate to strong westerly winds. These conditions will be building fresh slabs in leeward terrain.
A weak layer of surface hoar buried 40 to 90 cm has been the cause of numerous large avalanches this week. Remote triggering is a concern and avoiding overhead hazard is recommened.
A widespread natural avalanche cycle occurred earlier in the week, with very large avalanches up to size 3 reported. Numerous human and remote-triggered avalanches up to size 2.5 were also observed. While activity has generally decreased, several avalanches up to size 2.5 were reported on Friday.
This activity confirms a reactive weak layer with ongoing potential for remote triggering—conservative terrain choices are strongly recommended.
A weak surface hoar layer buried 40 to 90 cm is the primary concern in the region. It has been the failure layer in many recent avalanches. On south-facing slopes, this layer is a sun crust.
Up to 10 cm of new snow is forecast for Sunday. Combined with moderate to strong ridgetop winds, these conditions will build fresh slabs on leeward slopes at upper elevations.
A melt-freeze crust can be found down 100 to 150+ cm. It is thin or absent in alpine terrain but thicker and more widespread at treeline and below. Triggering this layer is considered unlikely at this time.
The lower snowpack is generally well-bonded and consolidated, with multiple crust layers present.
Saturday Night
Mostly cloudy. 1 to 3 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -5 °C.
Sunday
Cloudy. 5 to 10 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -4 °C.
Monday
Mostly cloudy. 5 to 15 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 2000 m.
Tuesday
Partly cloudy. 0 to 5 mm of rain at treeline. 40 km/h west ridgetop wind. Treeline temperature 3 °C. Freezing level rising to 3200 m.
More details can be found in the Mountain Weather Forecast.
