Avalanche
- Trigger Type
- Natural
- Vertical Fall
- 305 m
- Avalanche Type
- Soft Slab
- Avalanche Problem
- Persistent Weak Layer
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.
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.