Observations – Arctic Valley Backcountry

Obvious signs of instability:

• Small, D1 skier triggered wind slab on NW aspect steep, upper elevation terrain (potential for larger wind slabs up to D2 apparent)
• Cracking in wind loaded areas of denser snow

Weather:

• Partly cloudy skies with no precip
• Temps in low to upper 20s (increasing with elevation due to inversion)
• Light westerly breeze

Surface conditions:

• ~4″ loose, dry snow from Sunday in areas unaffected by the wind
• Deeper, denser (1F to 1F+) areas of wind affected snow
• Upper elevation areas of exposed old, hard wind slab
• Small standing, intact surface hoar in the most wind sheltered areas
• Lain over or blown away surface hoar in most areas
• Weak radiation recrystallization crust on the most solar aspects

Discussion:

Quick after work trip to Arctic Valley to assess steep, upper elevation, leeward terrain thought to have the best potential snow for riding; but suspect due to wind loading.  Some cautious turns, a snowpit, and stability test results raised some serious concerns:

View west from pit location:

Pit after being filled back in:

Gordon Lyon ridge view:

South Fork view from Arctic Valley:

Rendezvous Peak:

Sunset over the missile silos: