Observer Name
Bill Nalli
Observation Date
Sunday, December 20, 2020
Avalanche Date
Sunday, December 20, 2020
Region
Salt Lake » Big Cottonwood Canyon » Days Fork » Hide A Way Park
Location Name or Route
Silver-Days Hideaway Park
Elevation
10,100'
Aspect
Northeast
Slope Angle
34°
Trigger
Skier
Trigger: additional info
Intentionally Triggered
Avalanche Type
Soft Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Depth Hoar
Depth
16"
Width
20'
Vertical
100'
Comments
Travel was up Toledo Bowl to Flagstaff Peak, Emma Ridge, West Bowl, out Days Fork Quicksilver. Lots of aspects and elevations crossed. S aspects in Toledo and Emmas have HS 30-40cm. Rocky. West aspects are stripped up high and rotten down low. NW through NE to E aspects are suspect especially as the slope angle approaches 35 degrees. Collapsing is still happening as this persistent weakness gets it's first real test.
I triggered this small avalanche from a 30 degree slope that failed and released where the slope angle approached 35 degrees. NE aspect at 10,100'. A quick crown profile indicated two important things. (1) I was unable to isolate a column along its flanks even after the slope had collapsed, and failure was in the well documented December depth hoar, but (2) much weak snow still remained in the bed surface.
Comments
The previous avalanche released adjacent to a N that occurred on Dec 18 on NE-facing slope along the West Bowl / Days Fork ridge (pic). Both small but they're an indication of the type of weakness we'll be dealing with for a while.
Comments
Very Poor structure abounds. This snow profile was taken at 10,200', E-facing West Bowl. HS 63cm. The Mid-Dec. slab varies from 30-40cm thick and is resting on top of F hard 4mm depth hoar. Stability tests continue to fail easily and propagate along the entire column. There's no wishing this avalanche problem away. It will be with us until either it avalanches or gets compressed by lots more snow.
Coordinates