Conditions will remain dangerous after the storm. The new snow needs time to strengthen.
The weak layer from early December is of greatest concern in areas with shallow, thin-to-thick snowpacks and on wind-loaded north and east-facing slopes.
30 to 50 cm of new snow from Wednesday has formed reactive slabs, especially on wind-loaded slopes.
Wednesday's storm likely caused a natural avalanche cycle, with preliminary reports finding storm slabs were reactive to explosives.
During the warm weather on Sunday, a few large to very large (size 2 to 3) persistent slab avalanches occurred on southeast and northeast aspects. We are uncertain how these slabs responded to the latest storm.
30 to 50 cm of snow fell on Wednesday, with southwest wind depositing more in lee areas. A layer of surface hoar is buried 50 to 90 cm deep, observed on all aspects and elevations. Buried weak layers from December, 150 to 250 cm deep, include crusts, facets, and/or surface hoar, and continue to produce large avalanches.
Wednesday Night
Clearing skies with 2 to 4 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -12 °C.
Thursday
Mix of sun and cloud. 20 km/h southeast ridgetop wind. Treeline temperature -15 °C.
Friday
Mostly cloudy with 1 to 3 cm of snow. 20 km/h northeast ridgetop wind. Treeline temperature -15 °C.
Saturday
Mix of sun and cloud. 30 km/h northeast ridgetop wind. Treeline temperature -20 °C.
More details can be found in the Mountain Weather Forecast.
