Observer Name
Bo Torrey and Andrew Nassetta
Observation Date
Sunday, March 11, 2018
Avalanche Date
Sunday, March 11, 2018
Region
Salt Lake » Big Cottonwood Canyon » Guardsman Pass area
Location Name or Route
Caribou Basin
Elevation
9,600'
Aspect
Northeast
Slope Angle
40°
Trigger
Snowmobiler
Trigger: additional info
Unintentionally Triggered
Avalanche Type
Hard Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Facets
Depth
5'
Width
350'
Vertical
250'
Caught
1
Comments
Overview of the slide. Large debris pile ending in a boulder field. This ride was lucky to have escaped this slide unharmed. Earlier in the day we were checking out a slide just on the other side of the ridge that had occurred 24 hours prior, same aspect, elevation and wind loading pattern. Nearly 7 days after our last significant load of snow and people are still triggering deep avalanches that are breaking into old snow layers near the ground.
Comments
You can see the riders track onto the slope here. This is where he triggered the avalanche.
Comments
Crown was 1' to 6' deep. Obvious "step down" avalanche. Meaning that the avalanche initially failed on one weak layers and as the weight of that snow began to move down the slope it triggered a secondary avalanche deeper in the snowpack.
Coordinates