December 11
Willow heights, Monitors
Elevations, slope angles and aspects
7800-10200', angles approaching 35°, north and west facing.
Snow conditions
Total snow at Willow trail head was 4-12".That total remained the same to the base of Will's hill. The change was to recent snow over a stout crust. The recent snow layering was light density and small facets. In sheltered, non wind affected terrain, that snow would sluff on the crust if, the angle was steep enough. Sluffs were not moving very far.
Upper elevations were wind effected from the variety of different wind directions leaving conditions ranging the gamut, once again.
A little historical perspective.
South Monitor-Dec. 11
Nov-22 slide
Weather
Partly cloudy skies, moderate temperatures and light wind from the west.
Avalanche activity
A zoomed view of the slides in Silver Fork, west bowl. The most north facing, sheltered and shady, has released several small slides on, what appears to be, faceted snow layering.
West Monitor
Wind drift initiated by walking the ridge above. Forty or so feet wide, depth from a coupla inches to over a foot.
Release was collapse on light density-small facets over stout crust.
Evaluation
The light density snow from December 7-8 has experienced wind and temperature gradients. The result: complex variation in coverage.
Slopes have been scoured and drifted, small surface-near surface faceting is a patchwork quilt.
Areas sheltered from wind and sun have more advanced recrystalized layers. The wild card is crust.
Weather guessers have a large storm incoming. Bonding of new snow to the old surface is questionable. A poor bond would result in new snow slides on underlying crusted snow below light density. Increasing the load, with good bonding, could easily result in collapse failure of older snow layering and larger slides.
Wouldn't expect any sort of clean out and may end up with lingering deep slab instability because of the extensive crusts bridging over weaker faceted snow layering.
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