Avalanche

Glen Lake

Arden FeldmanBitterroot
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Quick report

Cracking
specific
Collapsing
isolated

We found widespread wind affected snow from the strong west wind event on Wednesday (12/18). Snow surfaces included wind board, wind crusts, sastrugi, sun crusts, and some soft powder in protected spots. We observed two large natural avalanches on an upper elevation east aspect near Ranger Peak that were likely wind slabs that released during the wind event on Wednesday. We observed some cracking and collapsing in wind slabs today, but overall, wind slab sensitivity is decreasing and felt stubborn. Buried facets in the middle of the snowpack seem to be adjusting to the load above, but they are still present and create a poor structure. 

It was warm with some sun today, and the snow at middle and lower elevations got wet and sticky, especially on more southerly aspects. The snowpack is still thin, especially at middle and lower elevations, and there are still many lurking early season hazards. 

We observed two large natural slab avalanches that likely released during the wind event on Wednesday (12/18). We observed minor cracking in wind skins and wind slabs in wind affected areas. We also experienced one significant whumpf while skinning near the edge of a lake.

Weather

Air Temp
37
Cloud Cover
scattered
Wind Loading
light
Snow Avail For Transport
small smounts

It was a gorgeous day with warm temperatures, partly cloudy skies, and generally light winds. Near the summit of Glen Lake Peak, moderate SW wind gusts were transporting light amounts of snow.

Snowpack

We dug a snowpit on a wind protected NE aspect at 7900 ft. The total snow depth was 120 cm or 47". Snowpack tests did not produce any significant, propagating results. However, we did find a weak layer of small grained facets buried by a nearly 2 foot thick slab above. 

Avalanche

Size
D2 R2
Aspect
E
Trigger
N
Elevation
8300 ft

We observed two large natural slab avalanches on an upper elevation east aspect near Ranger Peak on the Bitterroot crest. They were likely wind slabs that released during the strong wind event on Wednesday (12/18).