Observer Name
Greg Gagne - Dave Pease
Observation Date
Tuesday, February 16, 2021
Avalanche Date
Tuesday, February 16, 2021
Region
Salt Lake » Mill Creek Canyon » Porter Fork » Main Porter
Location Name or Route
Main Porter Fork
Elevation
Unknown
Trigger
Natural
Avalanche Type
Soft Slab
Avalanche Problem
Persistent Weak Layer
Depth
Unknown
Width
Unknown
Vertical
1,000'
Comments
Ascended into Main Porter and stopped adjacent and below of the upper meadow, this large natural avalanche came down from the first slide path just above the upper meadow. The debris was as low as 8,200'. It likely ran at least 1,000' from the ridgeline above, breaking mature Aspen timber.
The photo marks an X at the toe of the debris, and the arrow shows the likely slide path.
We did see two separate dust clouds - about 5 seconds apart - and it is likely the first slide was smaller and it sympathetically released a larger slide. It is also possible the large slides paths further up Main Porter had ran.
The video was added on Thursday, February 18.
Comments
I was last in Main Porter on Jan 23 and noticed a very poor structure with ~60-75 cms of very weak facets and depth hoar at 9,500' - right at about the same aspect and elevation as the likely starting zone for today's natural.
Video
Coordinates