| Trigger | Skier | Remote Trigger | 0 |
| Avalanche Type | Hard Slab | Aspect | South Southwest |
| Elevation | 3900ft | Slope Angle | 40deg |
| Crown Depth | 3ft | Width | 60ft |
| Vertical Run | 900ft |
Avalanche: Hatcher Pass
Location: Marmot SW face
Mid-elevations, all aspects, highly discontinuous and shallow snowpack (HS 25cm-40cm), heavily scoured and loaded in isolated to specific areas, localized whumphing and shooting cracks. Persistent slab sensitivity stubborn to touchy.
Upper elevations, all aspects, in specific locations where winds deposited more continuous, thicker and cohesive hard slabs the persistent slab avalanche problem was more significant, up to 85cm (3 feet deep), averaging 45cm (1.5 feet deep). Persistent slab sensitivity touchy. Human triggered avalanches likely, remotely triggered avalanches possible.
Old raised tracks on some steep upper elevation slopes, sastrugi, supportable and breakable crusts and old wind slabs. Slabs begining to facet out, areas without cohesive slab are pure facets.
The gem for skiers or boarders would be finding a zone that lacks the slab and skiing pure square powder. We did not find it.
Avalanche Details
avg crown height 1.5 feet;
touchy trigger from low angle (30 deg) ridgeline
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | Yes |
| Cracking (Shooting cracks)? | Yes |
Observer Comments
Cracking an whumphing abundant. Localized up to 15 meters, depth 25 to 40 cm. Mod strength, Poor structure, high energy.
Recent avalanche same aspect and elevation, winds Jan 5?
Weather
Ta= -9.2C, Ts= -7C @ 3400', Calm, surface snow NSF 0.5
Snow surface
NSF, wind board 2-6" thick, wind exposed xtra fragile faceted crust
Snowpack
Old wind slab over weak mid-pack over extra weak depth hoar
Weak layer culprit
old MF with DH at 10 to 16 cm in pit profile
Ridge near trigger location
Crown
Hard slab blocks
ASc Marmot 7
ASc Marmot 8
ASc Marmot 6
ASc Marmot 9
Ax Profile Marmot Jan 6 2016
ASc Marmot 11 bed surface
ASc Marmot 10