Observer Name
Willem Frederik Groot
Observation Date
Wednesday, January 9, 2013
Avalanche Date
Wednesday, January 9, 2013
Region
Salt Lake » Lewis Peak
Location Name or Route
Lewis Peak
Elevation
9,200'
Aspect
North
Slope Angle
Unknown
Trigger
Snowmobiler
Trigger: additional info
Unintentionally Triggered
Avalanche Type
Hard Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Facets
Depth
3'
Width
100'
Vertical
200'
Comments
Snowmobiler was ascending the slope and hit an area just below the cornice where he stated he thought he hit "a void" and started loosing traction so he accelerated and felt himself hitting the top of the cornice. Snowmobiler did not realize he had touched off an avalanche until he looked back at the slope from the top of Lewis Peak. Avalanche left about a 3 foot wall at the top and moved relatively slowly. I was able to see it coming and move uphill out of it's path and take the attached picture. We know this slope wind loads and has avalanched in the past but it was a bit surprising in that it has been some time since we had fresh snow. All riders had airbags, beacons, shovels and probes in their possession and have taken training classes.
Coordinates