Quick report
- Red Flags
- Wind Loading, Cracking, Poor Snowpack Structure
2-3" of Large ~8mm graupel fell with the arrival of the cold front early afternoon. Observed small graupel "waterfalls" in steep rocky terrain pouring over cliffs.
This chute avalanched naturally sometime during the early December cycle. Debris piles were observed lower in the track.
Most slopes in this photo had evidence of avalanche activity from early December.
Snowpack
- Instability Comment
- <p>I traveled up the Flagstaff Ridge to look at slopes in Upper Days Fork and see how the snowpack was responding to the recent dry and warm conditions. During the early December storm cycle, each named ski run along the upper cottonwood ridgeline from <a href="https://wbskiing.com/2605"><em>Upper Days</em></a> through<a href="https://wbskiing.com/2598"> <em>Hideaway Park</em></a> avalanched at least once. Looking at the remaining snowpack in the Upper Days starting zone showed 4-6" of dry faceted snow remaining above a 2-4" basal ice on the ground. As snow reloads this (and similar) slope(s) I expect will avalanche again. Looking at the snowpack lower in the drainage on sheltered north-facing slopes around 9500' that did not avalanche showed a much different structure. There I found a snowpack that was moist to the ground. The weak layer near the ground was still reactive in <em>some </em>Extended Column Tests, but not all. While this moisture <em>could</em> facilitate strengthening if the weather remains active and the pack deepens, a return to cold, high-pressure conditions would likely weaken the snowpack further. Something to keep an eye on.</p> <p>While snow available for transport was limited, strong winds drifted snow along upper ridges onto north and east aspects. These winds occasionally reached into sheltered terrain, despite visible snow transport, I did not observe any fresh, sensitive wind drifts as of 4 PM.</p>
A layer of dust was noted on the snow surface before the arrival of the cold front. Large 8mm graupel improved riding conditions, especially on lower-angle slopes with supportable crust below. Pleasantly surprised. Despite the thin coverage, I found that south-facing slopes made for decent skiing with a supportable, pseudo-refrozen crust beneath and a bit of dense graupel above.