Avalanche: Lanes Leap

Observer Name
Bill Nalli
Observation Date
Wednesday, March 15, 2023
Avalanche Date
Wednesday, March 15, 2023
Region
Salt Lake » Big Cottonwood Canyon » 10420 » Lanes Leap
Location Name or Route
Lane's Leap
Elevation
9,600'
Aspect
North
Slope Angle
38°
Trigger
Natural
Avalanche Type
Soft Slab
Avalanche Problem
Wind Drifted Snow
Weak Layer
Facets
Depth
2'
Width
150'
Vertical
200'
Comments
While ascending the north ridgeline of Hidden Canyon we found two small natural avalanches that had failed sometime mid morning. The slab consisted of about 20cm of the latest new snow atop 30cm of 1F hard rounded grains from the 3/9 storm, The weak layer was another 10cm of small rounding faceted grains from 3/7-3/8. These north facing slopes are moderately wind loaded with a steep (38deg) upper section that flows into lower angle trees. They didn't travel very far but the biggest one was 150'wide and 60cm deep.
Comments
Upon exit we chose to descend adjacent to the larger of these two slides on a lower angle rib. It seemed the hazardous slope angle today was around 37deg and steeper. Along the ridge just below the cornice I spied a small relatively safe steep pocket to ski cut and produced this additional deep small avalanche. 60-80cm deep this time and it traveled' farther into the lower angle treed slope below.
All signs that today's instability was on the rise and all steep wind-drifted slopes were suspect.
Lastly, it doesn't feel like this particular weakness will settle very quickly and one should expect to continue to find similar avalanche issues for the next few days.
Comments
Not all steep slopes were as sensitive. I tickled the 37 deg top pitch of 10420' and no avalanche. This is a good reminder that its not all straight forward and there is variation in both the slab thickness and strength as well as the quality of the faceted weak layer.
Coordinates