Prolonged warming will keep persistent slabs at their tipping point. Manage this high-consequence snowpack with low-consequence terrain.
Southwesterly winds built wind slabs on leeward northerly and easterly slopes. If triggered, wind slab avalanches may step down to deeper layers resulting in larger avalanches.
Weak layers formed in January persist within the upper 100 cm of snow. The more the snowpack warms up and weakens over these layers, the more conservative your terrain selection should be.
In the past week, numerous natural and rider-triggered wind slab and persistent slab avalanches have been reported, up to size 3.
Evidence indicates wind slabs and persistent weak layers remain primed for human triggering. Similar activity is expected on Sunday with continued warm temperatures and potential for strong sun.
Read more in our Forecasters' Blog.
20 to 50 cm of settling storm snow rests on a weak layer of facets or surface hoar, while elsewhere it overlies a widespread crust. At lower elevations and on sun-exposed slopes, warm temperatures and solar radiation resulted in a crust or moist snow on the surface. Additional weak layers formed in January are found at varying depths within the upper 100 cm of snow. These include weak faceted snow, sun crusts on south-facing slopes, and surface hoar in shaded terrain. Otherwise, the mid and lower snowpack is generally well-settled and strong.
Saturday Night
A mix of sun and cloud. 5 to 20 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1500-2000 m.
Sunday
Mostly cloudy with up to 5 cm of new snow. 10 to 30 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1500 m-2000 m.
Monday
A mix of sun and cloud. 5 to 15 hm/h north ridgetop wind. Treeline temperature -3 °C. Freezing level rising to 1500 m.
Tuesday
A mix of sun and cloud. 10 to 30 hm/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level rising to 1500 m.
More details can be found in the Mountain Weather Forecast.
