Collapse on Mt Brown

Toured up Mt Brown looking for signs of wind slab or persistent slab instabilities 

• ~5” of fist hard recent snow at upper elevations with surprisingly minimal wind affect. Shallow drifts were unreactive to ski cuts
• A member of our group experienced one loud collapse on a flat ridgeline at 7800’. She was the 4th person to cross that slope. The ridge held a relatively shallow, scoured snowpack that was stiffened by the wind.
• We turned away from a large alpine bowl after identifying a low likelihood but high consequence persistent slab structure: 130 cm hard slab over 2mm facets around a crust. We descended benchier terrain where wind scouring had eroded much of this structure and consequences where smaller. As we descended into mid elevations on southerly aspects, we noted a very weak basal structure (fist hard, 2mm facets and soft crusts), but the snow above appeared to be too soft and shallow (<40 cm, F+) to have a reactive persistent slab problem.
• No recent avalanches observed or other signs of instability.