Quick report
- Aspect
- Northwest
- Red Flags
- Poor Snowpack Structure
- Elevation
- 3048 m
Spent a few hours this morning on uphill training at Brighton, but after one lap I went in to Hidden Canyon to look at the snowpack structure. Very easy to dig down to the weak snow at the ground. Most slopes I was looking at were thin (30-45 cms) but there wasn't enough of a slab on top of the faceted snow near the ground to cause concern. However, I did find one slope that had a thicker and dense slab on top and I was getting full propagation with extended column. I think most slopes currently have a Low danger, but any slope with recent wind-drifted snow has a Moderate hazard of avalanching to the ground/rocks/stumps/bushes. I don't think the current structure would support wide, connected avalanches, but more likely smaller pockets.
Caution: Snownerd alert! Few photos of 1-2 mm facets found down at the ground.
Video and discussion of weak snowpack structure found at 10000' in upper Big Cottonwood Canyon.
Snowpack
- Instability Comment
- <p>Weakest snow is the bottom 5-10 cms (2-4") in the snowpack that contains 1-2 mm basal facets and depth hoar. It is very easy to dig down to the ground in our thin snowpack and identify this layer. Above this weak layer the snowpack is settled decomposing fragments and a 4F-hard slab. In most of my pits I wasn't finding enough of a slab on top to create a concern, but on one slope on a N aspect at 10000' I found a deeper snowpack (closer to 60 cms/24"). This slope had drifted snow from earlier this week and a 30cm 4F slab sitting on top of the faceted layer. Performed a few ECT tests and got full propagation on isolation (ECTPV), or with two taps from the wrist (ECTP2). All Q1 quality shear failing in weak snow near the ground. </p>
About 2-5 cms (1-2") dense new snow and graupel sitting atop very thin rime crusts that formed this past week during a few riming events. Wind drifts that formed earlier this week were dense and no longer sensitive. HS ranges from 30-45 cms (12-18")