Dry snow may remain in high elevation northerly terrain however, this is also triggering weak layers is most likely. Manage this high-consequence snowpack with low-consequence terrain.
Previous southwesterly winds built wind slabs on leeward northerly and easterly slopes. If triggered, wind slab avalanches may step down to deeper layers, resulting in very large avalanches.
Weak layers formed in January persist within the upper 100 cm of snow. As temperatures cool, natural avalanche activity will likely taper off, but human triggering potential will persist. Keep your terrain selection conservative.
On Saturday, a skier remote triggered size 3, persistent slab avalanche was reported. This avalanche occurred on a northwest facing slope at 2050 m. Evidence indicates wind slabs and persistent weak layers remain primed for human triggering.
Explosive control in the region produced several persistent slab avalanches up to size 3.
Solar input and elevated freezing levels triggered a widespread natural avalanche cycle to size 2.5.
Read more in our Forecasters' Blog.
Above 1000 m, a few centimeters of snow overlies a melt-freeze crust, which extends to ridgetops on all aspects except northerly slopes above 1700 m where surfaces remained dry. Below 1000 m, the snow surface may remain moist.
20 to 50 cm down is a weak layer of facets/surface hoar or a crust. Additional weak layers formed in January are found at varying depths within the upper 100 cm of snow. These include weak faceted snow, crusts on south-facing slopes, and surface hoar in shaded terrain. Otherwise, the mid and lower snowpack is generally well-settled and strong.
Sunday Night
Cloudy with light flurries, 1 to 5 cm of snow. 10 to 25 km/h northwest ridgetop wind. Treeline temperature -5 °C. Freezing level drops to 1000 m.
Monday
A mix of sun and cloud. 5 to 15 km/h northwest ridgetop wind. Treeline temperature -2 °C. Freezing level rising to 1500 m.
Tuesday
Mainly sunny. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level rising to 1500 m.
Wednesday
A mix of sun and cloud with light flurries, up to 2 cm of snow. 20 to 35 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level rising to 1500 m.
More details can be found in the Mountain Weather Forecast.
