Northern Turnagain Arm – Penguin Ridge

Signs of Instability

• Subtle whumpfing and cornice settlement near Penguin Peak
• D3 human triggered wind slab SSE aspect near Penguin Peak
• D1 human triggered wind slab N aspect near Penguin Peak

Weather

• Mostly sunny skies
• Calm-Moderate NW winds
• Mountain temperatures in the upper single digits

Surface Conditions

• Dry, variably wind affected snow in the upper elevations on all aspects (softer in more protected areas)
• Variable sun crust on lower elevation south to west aspects

Avalanche Concerns:

Friday’s northerly winds have affected the pristine powder from the previous two storms.  Soft, dry, and pleasant powder still abounds in sheltered areas.  Variable windboard can be found along ridges and near peaks.  Wind slabs reactive to human triggering were found on both northerly and southerly aspects along the Penguin Peak ridge.  Leeward south facing slopes near the ridge had been heavily loaded and produced widely propagating wind slabs.  Windward north aspects near the ridge harbored thin, soft wind slabs that weren’t as sensitive and long running.

Human triggered wind slab (SS-ASu-R2-D3) SSE aspect starting at ~4200′ and running ~3500′:

Randoman sighting: