Observer Name
Darce Trotter/ Steve Cote
Observation Date
Monday, February 18, 2013
Avalanche Date
Sunday, February 17, 2013
Region
Skyline » Huntington Canyon » Left Fork Huntington Canyon » Seeley Canyon
Location Name or Route
Seeley Canyon, Wasatch Plateau
Elevation
10,000'
Aspect
East
Slope Angle
40°
Trigger
Natural
Trigger: additional info
Repeater
Avalanche Type
Soft Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Facets
Depth
2'
Width
150'
Vertical
300'
Comments
Came across this in our travels today. This area is a repeater, the usual suspect, ENE facing, exposed, wind stripped, shallow pack, and very rocky. Side by Side naturals occurred overnight or during yesterdays wind event that accompanied weak cold front. We were really surprised to see any activity, and while is was very fresh, our objective was across the valley, NW facing, more sheltered, and certainly the fattest snowpack in the area.
Looking on the fetch to the south, a significant row of trees may be a catalyst for this path, slowing the snow so it loaded on this steep rocky gullies , and while several other exposed ridgelines had been blown to the dirt from SW winds, that was not the case here. This is the only activity we saw all day long, where we skiied is included in our ob.
Obviously faceting in the rocks is the weak layer, the pictures tell it all. Recent wind loading yesterday and overnight, failed on facets in rocky shallow area.
FORECASTER COMMENTS: Darce is on it here. I've noted numerous areas where the wind has stripped the snow creating a shallow snowpack that is much weaker than the deeper areas. This is tricky as these shallow areas become buried and there are no obvious signs that they are holding a shallow and weak snowpack under the newer snow. The only way is to follow certain slopes throughout the winter so you know what the structure is and how it progresses. Otherwise, it's a 'crap shoot'. I am also a bit surprised to see natural activity but the winds no doubt picked up enough to transports snow on Sunday.
Comments
closer look, this same slope was tested last year by several snowmobiles at at time and the video was part of Craigs observation that day.
Comments
Note the blown in snowmobile track in steep gully to lookers left, got away with that.
Comments
Shameless plug for UAFC
Coordinates