Quick report
- Aspect
- East
- Red Flags
- Recent Avalanches, Wind Loading, Poor Snowpack Structure
- Elevation
- 2896 m
- Slope Angle
- 35°
- Red Flags Comment
- <p>I observed recent avalanches on East aspects that most likely occurred on Jan 2. These slides broke on buried facets and ran on a hard crust at the ground. I observed moderate snow transport onto leeward slopes. I found poor snowpack structure in an East facing pit at 9,480 ft.</p>
Photo 1: Crowns in the East facing bowl off of Horsehead Peak. The two crown lines highlighted on the left side are harder to notice. The bed surface and debris pile has been covered up by recent wind loading. The crown and track on the right are easier to notice.
Photo 2: This avalanche also occurred on an East face and buried the switchbacks on the summer road up North Creek. These switchbacks are a popular route for snowmobiles.
Photo 3: I dug a pit adjacent to the flank of the avalanche that crossed the road. The red line indicates where I got a failure with propagation (ECTP 26). The avalanche would have failed on this red line. From this photo it is easy to see that these avalanches are taking out the entire season's snowpack. These avalanches would be deep and deadly.
Video Clip: This short video shows the full track of the slide that buried the switchbacks. The debris piled up in the creekbed at the bottom.
Snowpack
- Instability Comment
- <p>The Abajo range had a very weak and shallow snowpack prior to this last big storm. I found facets sitting on top of a hard crust at the ground. Almost three feet of snow stacked up in a short period of time on top of this weak snow. The hard crust at the ground makes an excellent bed surface. The recent avalanches I observed failed on these facets and slid on the crust at the ground. I got failures on this same layer in an Extended Column Test, ECTP 26. This tells me that this weak layer is still capable of producing avalanches. The snowpack in the Abajos needs more time to heal. This problem is most pronounced on aspects that face NW-N-NE-E. </p>
It was pretty warm today with intermittent sunshine, this was making the surface snow become dense.