Observation: 10420

Observation Date
12/11/2018
Observer Name
Bruce Tremper
Region
Salt Lake » Big Cottonwood Canyon » 10420
Location Name or Route
Peak 10420
Weather
Sky
Clear
Wind Speed
Light
Weather Comments
Beautiful bluebird day up above a thick, gloomy, stratus layer of clouds and smog over the valley.
Snow Characteristics
Snow Surface Conditions
Dense Loose
Faceted Loose
Snow Characteristics Comments
Snow surface still remarkably good in soft, recrystallized snow on shady slopes. Most slopes are tracked up and the snowmobiles have really hammered the east facing side of Peak 10,420 and it seems like people have been loving the Wasatch to death, which you would expect after a lean year last season. Coverage is remarkably good for the early season with about a meter or more of supportable, dense snow on most slopes. Still very good snow on all the shady terrain that has not been tracked up and we found quite nice "loud powder" in the north facing trees back down the Guardsman's trailhead. Overall, just a delightful day to be out and about without the crowds.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #1 Comments
It's a dormant, persistent slab problem on all the shady slopes--mostly north through east. Everything has been thoroughly tracked up without incident these past few days. We skied the steep east face of Peak 10,420, which is usually a scary place to be with a persistent slab problem but it's been thoroughly hammered by snowmobilers and skiers.
Snow Profile
Aspect
North
Elevation
9,400'
Slope Angle
30°
Comments
Did a quick pit down off the west ridge out of the wind zone. It seemed very representative of the rest of the snowpack in the area. Yes, the depth hoard is still in the basement but I had to hammer on it fairly hard to get it to propagate. Same results in two Extended Column Tests with propagation at 22 or 23 (full arm blows to the top of the column). So it's still there, just difficult to trigger--a "dormant persistent weak layer" as we call it. But we have to remember that dormant means that it can easily be reactivated by additional loading, which is supposed to arrive tomorrow. It also means that you can still find slopes where you can trigger an avalanche, it's just that they are relatively isolated.
Tomorrow's danger rating depends on the amount of loading from new and/or windblown snow.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
None
Coordinates