Lake OHara, September 11th and 12th.
Nil slab avalanches observed in the area, lots of sloughing in steep terrain.
Up to 60 cm. thick, hard windslabs were found on the Opabin glacier in any lee
features on September 11th. No whumphing or cracking but I still retreated at
the base of the 40 degree slope to Opabin Pass. On the 12th Schaeffer bowl had
much more settled moist snow and the slab was not an issue. I would assume snow
stability improved somewhat below 3000m with warm weekend temperatures. However
hard slab avalanches still concern me above 3000m in the OHara area. South
aspects got enough sun to be noticeably drier by today. Still lots of rockfall
to come when this storm snow starts to melt off the steep rock features. Grassi
ridge wet for at least one more day.
Larry Stanier
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