Quick report
Reconnaissance mission into Granite Canyon to gather data and check conditions. We found variable skiing, with a breakable crust present from the Christmas rain event, along with firm bed surfaces, and very thin coverage down low. Also observed a significant rockfall event that came off the cliffs in the lower canyon, likely with the rain. The exit was generally impassable with insufficient snow coverage for travel. Rescue from the ground would likely not be possible.
Snowpack
We dug a pit on a N aspect around 8800 feet. What we found was very unusual for December in the Tetons. The upper snowpack was a variety of crusts and abnormal melt forms. Snow at all depths was very moist and easily compacted. Due to the HS at this location, we suspect it had slid previously. The rain crust buried on 12/17 was unreactive to tests, though a variety of other layers produced results. The only propagation we observed was in the upper snowpack. See attached pit diagram.
Avalanche
- Size
- D2 R2
- Type
- WL
- Count
- 2
- Aspect
- N
- Trigger
- N
- Elevation
- 8000 ft
Significant wet slide cycle observed. Believed to have occurred with the rain event Christmas Eve/Morning. Slides up to D2.5. None of the debris hit the creek bottom due to an abundance of small trees and willows at low elevation.