| Trigger | Snowmachiner | Remote Trigger | 0 |
| Avalanche Type | Hard Slab | Aspect | West |
| Elevation | 2000ft | Slope Angle | unknown |
| Crown Depth | 5ft | Width | 500ft |
| Vertical Run | 800ft |
Avalanche: Other Regions
Location: Grandview
Moose Pass to Grandview.
Avalanche Details
1 snowmachine- triggered avalanche (1st photo) and several other deep wind slab pockets. Spoke to party and avalanche was triggered from below, lookers left side. Lookers left pocket then sympathetically triggered lookers right (larger) avalanche. May also have sympathetically triggered a wind slab above. Nobody caught.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | Yes |
| Cracking (Shooting cracks)? | Yes |
Observer Comments
Felt multiple collapses throughout the day. 1 snowmachine-triggered avalanche, 2 smaller (deep) wind slabs and 1 larger wind slab that stepped down. See photos.
Note: all avalanches were in the 2000-2500' range and all had a westerly component.
Weather
Snowing lightly in the morning and clearing throughout the day. Winds were calm. Low to mid-30's F.
Snow surface
3'+ storm snow settled to about 2.5'. Consistent powder. Noticing sun affect late in the day on Trail Lake.
Snowpack
Did not dig formal pit today. Snowpits from previous 2 days in Turnagain make me think that weak layer was facets/ bsh (Jan.21) below storm snow interface.
Many sled-cuts on small terrain yielded no results but recent avalanches speak for themselves. We kept our terrain choices very manageable today.
Snowmachine triggered avalanche from lower lookers left (remote trigger).
Same avalanche as above. Notice wind slab above and lookers right may have been triggered sympathetically. photo: Sebastian Landry
photo: Sebastian Landry
Natural wind slab, stepped down to weaker layer mid-slope.
Small (deep) wind slab at ~2200' on West aspect. 6-8' deep.