Grand Mesa
AvalancheBrandon Levy ยท Jan 4, 2023
Weather
It was mostly sunny and the temperature was cool--in the teens. The wind was light from the northwest.
Snowpack
Douglas Pass received 53" of snowfall from December 28th to January 4th. This snow fell on a melt-freeze crust which was observed to be fairly discontinuous across the south-facing slopes above SH139 on December 20th. A profile on the south-facing slopes above the road at a location called Pipeline Face revelead small-grained facets underneath the melt-freeze crust. An extended column fractured on this layer after 27 taps (ECTP27 down 50cms on 2mm FC). There is a lot of snow on the trees on Douglas Pass and the high density snow combined with the rime event plastered snow into steep start zones above the road that would typical shed loose dry avalanches into the ditch. The snow depth in the south-facing paths is about 2.5' or less even after the recent 4.5' of snow mainly due to the strong southerly winds that accompanied the storm. Probing on north-facing slopes confirmed this observation and I am confident there were larger-grained faceted grains near the base of the snowpack on north-facing slopes prior to this large storm series.
Avalanche
Several small loose dry avalanches occured this morning to the ditch on SH139 as the sun finally appeared on Douglas Pass. There were several small avalanches to the road during the extended closure. Many of these slides had trees associated with them with treefall possibly the triggering mechanism.