Avalanche
- Slab Width
- 6 m
- Weak Layer
- Facets
- Trigger Type
- Natural
- Avalanche Type
- Soft Slab
- Slab Thickness
- 25 cm
- Start Zone Aspect
- North
- Avalanche Problem
- New Snow
- Start Zone Elevation
- 2530 m
We traveled from North Ogden Divide to Chilly Peak between 6,500–8,500 ft, primarily on SE–NE aspects. We observed multiple naturalvalanches (SS-N-R1-D1) on steep (≥35°) E–N facing slopes between 8,200-7,200ft mostly below cliff bands. These likely occurred during the previous day’s warming event. Avalanches appeared to initiate from roller balls and in several cases stepped down to a mid-storm density change or the new/old snow interface. Debris piles were small with limited runout.
We found 3–6 inches (8–15 cm) of high-density new snow, largely composed of graupel, on all aspects, with greater accumulations on wind-loaded E–NE–N slopes above 7,500 ft. A pronounced mid-storm graupel layer forms a density inversion that shears easily in hand pits. Snowpack structure varied by aspect and elevation: SE–S-W slopes held little prior snow, though melt-freeze crusts (MFcr) underlie the new snow where present and bonding appeared good on E aspects during informal testing. On shaded northerlies, 4F–F hard rounding facets exist beneath the new snow and represent the primary weak layer of concern.