Small reactive wind slabs (size D1) on Silver Peak.

Location Name: 
Silver Peak
Cabin Creek, Deep Creek, or Pole Creek Area
Date and time of avalanche (best estimate if unknown): 
Wed, 01/08/2020 - 12:45
Location Map: 
United States
39° 13' 25.7232" N, 120° 14' 36.7224" W

Red Flags: 
Recent loading by new snow, wind, or rain

Observation made by: Forecaster
Avalanche Observations
Avalanche Type: 
Trigger type: 
Crown Height: 
Less than 1 ft
Weak Layer: 
New/old snow interface
Avalanche Width: 
Near Treeline
7 900ft.
Bed Surface: 
Old Snow
Avalanche Length: 
Number of similar avalanches: 
Number of people caught: 
More detailed information about the avalanche: 

We went to Silver Peak today to look for the wind slabs that we expected had formed last night with new snow and wind. We found weak new cornice formations along the ridgetops that cracked easily under the weight of a person. The wind slabs below these cornices did not extend very far downslope. Descending off of the ridgetops we were able to intentionally trigger 5 small (size D1) wind slabs in pockets of wind drifted snow in near treeline terrain. Once we were down below the near treeline areas of wind exposure and deeper into the wind protected below treeline zone, we no longer encountered wind slabs or any other signs of instability.

The wind slabs that we triggered today had crowns in the 4 to 8 inch range and all failed just above the Jan 4 rain crust on very low density new snow (F- hard) at the old/new snow interface with DF crystals with some very minuscule amounts of faceting. The overlying slab of new snow increased from F- hard at the base to 1F hard at the surface. The avalanches triggered were mainly on a N aspect around 7,900' with one on an E aspect at 7,600'.

Avalanche Photos: 
Avalanche observation video: 

Small reactive D1 wind slabs

Weather Observations
Blowing Snow: 
Cloud Cover: 
75% of the sky covered by clouds
Wind Speed: 
Wind Direction: