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Observation: Copleys Canyon

Observation Date
2/5/2016
Observer Name
Toddeo
Region
Southwest » Pahvant Range » Chalk Creek » Copleys Canyon
Location Name or Route
Pahvant Range - Copley Canyon
Weather
Sky
Few
Wind Speed
Calm
Weather Comments
Calm day with a few clouds, warm south half of the compass will have a crust tomorrow.
Snow Characteristics
Snow Surface Conditions
Powder
Faceted Loose
Damp
Snow Characteristics Comments

Snow surface is holding up well on the north half of the compass. South half will have a crust tomorrow. Surface hoar in many areas, larger on lower elevation slopes

Red Flags
Red Flags
Recent Avalanches
Rapid Warming
Poor Snowpack Structure
Red Flags Comments
Red flags observed today include a large natural during the last strom cycle in north facing Copley Canyon. 700 vertical and 500' wide, i was able to access a low angle portion of the hangfire, likley ran on facets which are above the base of the snow pack, see profile below. Temps were warm enough to raise concern on south aspects.
Avalanche Problem #1
Problem
Wet Snow
Trend
Same
Problem #1 Comments

wet slabs may be my primary concern with forecasted warm temps.

Moderate to possibly considerable.

Avalanche Problem #2
Problem
Persistent Weak Layer
Trend
Same
Problem #2 Comments

After observing a 4 finger hardness layer of facets in Copley Canyon concern me on north aspects that have not run. Based on an ECTP of 30, these may be hard to trigger but with bad consequences.

Moderate X to possibly considerable in the upper elevations.

Snow Profile
Aspect
North
Elevation
9,200'
Slope Angle
25°
Comments

Of note in the profile are the facets/density inversion above a strong basal layer. The ECTP took force but still propogated. Photo of pit below, basket is on shear plane. Next photo shows top of slide path with pit location. This area was above the area that ran, I don't think it was steep enough. Third photo is tension crack next to pit.

Photos below are the slide path, upper and lower portion, As I have been finding there are some big paths in this range! I avoided the starting zone by sneaking in on an easterly aspect and was skiing and breaking trail back up the path on debris. Third photo is pile on mid path tree, a good indicator of activity. I avoided the steeper portions which have slope angles at least 40 degrees. Based on hand pits, the facets appeared to be cleaned out in the area I skied, otherwise I would have avoided the whole thing.

Photos below. Tension cracks on a north facing slope on the Mountain Sheep Canyon Ridge, my advice is not to ski out of this canyon, heinous bushwhacking.

Photo below, Pahvant Butte, with the snow cover in this area it might be possible to do some volcano skiing with out driving to the west coast!

Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate