Observer Name
Ross
Observation Date
Saturday, February 8, 2025
Avalanche Date
Saturday, February 8, 2025
Region
Salt Lake » Big Cottonwood Canyon » Brighton Perimeter » Snake Creek
Location Name or Route
Snake Creek East Bowl
Elevation
9,800'
Aspect
East
Trigger
Snowmobiler
Trigger: additional info
Unintentionally Triggered
Avalanche Type
Soft Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Facets
Depth
2'
Width
150'
Comments
This was reported by B on 2/9 as a natural slide in Snake Creek, but was triggered by snowmoblie on 2/8. I thought the person who triggered was going to report it, so I didn't. Initiation zone was approx 35 degree shallow snow over rocks, and stepped back up slope into steeper more wind loaded area. Based on depth , I'd say is a repeater since it went to the ground. another similar repeater slope just to the east in Caribou also sled triggered slid to the ground 2/8.
Comments
Via B -
Crown depth 74cm, HS 120cm; Structure of Slab from top down to bed surface: 22.5cm of Fist Hard Light Density New Snow, 30cm of 4 finger grauple, 15cm of Knife Hard Wind Slab, 6.5cm of 4 finger plus grauple, Thin Layer of .5mm facets (Weak Layer for initial failure); Bed Surface: 2cm of Pencil Hard Ambiant/Melt Freeze Crust (from last weeks warmup)
Avalanche appeared to initially release on the Thin Layer of facets diretly above the Ambiant/Melt Freeze Crust and then immediately step down to a 10cm Fist minus layer of 1 to 1.5mm advanced facets.
There were snow machine tracks below the runout and they may have remotely triggered this slide. But more likely this slide was triggered during the final round of snow yesterday afternoon when the PI was Intense. There was no obvious sign of Wind Loading in the upper layers, just the Fist hard new snow. Finally there was 10cm of light density snow on the bed surface, so this helps date the timing of the slide.
Coordinates