Grand Mesa

Avalanche

Brandon Levy, Polly Layton · Dec 13, 2020 · Grand Mesa

Weather

Calm and clear with cold morning temperatures increasing throughout the morning from negative single digits to mid 20's by the time we left the Skyway area around noon.

Snowpack

Between 12/11 and 12/13 plow ops recorded 18" of storm snow at the Skyway roadside weather plot. The new snow is relatively un-cohesive and soft where not impacted by the mostly southwest winds during the storm. In the most wind effected location above the Cliffs near and above #4 the new snow was slightly more wind effected and resistant; however, the underlying snow was not as weak as expected. A faceting melt-freeze crust and sintered facets below marked the 12/11 interface / layer and was unreactive in instability tests (both long and small column). The snow near the ground was the weakest layer at the location observed.

Avalanche

During the 12/11 to 12/13 storm thin soft slab avalanches released from the upper end of the Cliffs. Crowns are almost obscured. Plow triggered soft slab occurred at Aspen Bank this morning to the ditch.