Quick report
- Red Flags
- Wind Loading, Poor Snowpack Structure
Primary focus of the day was looking at the snow surfaces, how well the new snow was bonding with the old snow surfaces and any obvious signs of instability. This storm was mostly well-behaved, with decent bonding on both N and S-facing slopes we observed. The snow from our previous storm system more than a week ago—that became wetted and soft when we were riding here about a week ago—luckily consolidated and refroze with the colder temps this storm rode in on.
The result was a (mostly) supportable structure underneath the 6-8" of new storm snow, which made for enjoyable riding. In isolated areas, the unlucky rider could still pop through to the faceted snow below (Dry January Layer) and get pretty stuck. While we did not observe steep terrain, our plan was to not enter avalanche terrain that looked wind loaded—like Whiskey and Beer Hills—and steep slopes on the N half of the compass when the DJL may still release a large slab.
Photos:
#1: Wind-drifted snow was our primary concern, both on steeper slopes and even in flatter areas with lower-vis conditions
#2: Snowpack structure was mostly supportable above the DJL. Mostly.
#3: Machine ski pen was mostly 6-8"
#4: The storm came in on the wetter side, especially trending into the afternoon. Rimed PP and graupel fell, with rime decorating any tree or tower in sight.
#5: HST 6-8"
Snowpack
- Instability Comment
- <p>The primary concern and problem in our travels. More below in Comments.</p> <p>The DJL certainly exists here, with a strong over weak snowpack structure. However, the consolidation of the previous storm snow from more than a week ago into a supportable slab made it much harder to have a machine penetrate and affect that weak layer. This would mean the PWL is trending more stubborn, however we still won't be stepping out onto steep slopes on the N half of the compass with that structure. </p>
Generally 6-8” of low to medium density snowfall across most of the Monte Cristo zone. A mixture of stellars, rimed particles and graupel. Overall supportable in most areas, by the end of the day the snow surface was beginning to become damp and chunks of the road that were covered in the morning were melting out. Wind-textured surfaces along ridgelines and sub-ridges, with some wind features (holes, cornices, pillows) causing for some extra caution with low-vis.