Observations

Arctic Valley – Backcountry North Bowls

Red flags (obvious signs of instability):

• Pluming off 5000′ peaks early afternoon, widespread blowing snow by late afternoon
• Subtle “whumphing,” or collapsing, in isolated areas

Weather:

• Partly cloudy to obscured skies with passing showers of very light snow becoming steadier by late afternoon
• Light wind with moderate gusts early afternoon becoming steady moderate by late afternoon
• Temps in the upper 20s

Surface conditions:

• A few inches of soft powder in sheltered areas, with about an inch dusting of fresh on top
• Rock, tundra, or hard wind slab dusted with a bit of sticky fresh in exposed areas
• Variable

Snowpack:

3306′, 294* NW aspect, 29* slope, 75cm HS, ETCP 29 Q3 @ 38cm (P- wind slab on 4F+ facets), CTM 12 Q3 @ 63cm new-old interface (fresh snow wind slab on last weekend’s faceted powder), CTM 20 Q2 @ 35cm (same layer as ECT failure but fracture plane slightly deeper in faceted layer)

~3900′, WNW aspect, 33* slope, 96cm HS, ECTP6 Q3 @ 84cm (fresh snow wind slab on last weekend’s faceted powder – see 2nd photo below of failure plane), ECTP18 Q2 @ 66cm (P wind slab on 4F facet layer ~10cm thick), ECTP24 Q2 @ 36cm (failure on heavily faceted layer of chains and depth hoar)

Rain-snow line @ ~1000′ at 5ish pm.