Wind Slabs and Wind Scouring on Silver Peak

Location Name: 
Silver Peak
Region: 
Cabin Creek, Deep Creek, or Pole Creek Area
Date and time of observation: 
Tue, 03/22/2016 - 11:30
Location Map: 
United States
39° 13' 34.1868" N, 120° 14' 21.3612" W
US


Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain

Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

15 to 30 cm of new snow existed above 7000 ft. in the Silver Peak area. Below this new snow rain crusts and wet snow existed. Hand pits and observations showed small wind slabs resting on top of lighter snow in wind loaded areas and less cohesive snow in sheltered areas. A ski cut on a small wind loaded NE facing 35-38 degree test slope in near to below treeline terrain did cause a small (10cm) wind slab failure on that slope. At the higher elevations along the east ridge of Silver Peak between 7800 ft. and 8200 ft. the winds had already scoured away some of the wind slabs on the N facing slopes leaving behind a firm and frozen rain crust.  Snowpit tests on a slope where a wind slab had not been scoured away at around 8000 ft. yielded ECTN results (39.223337, -120.243430). 

Below 7200 the snow was beginning to become wet and heavy by 1 pm. 

Photos 1 & 2: Wind scoured crusts and features along the E ridge of Silver Peak between 7800 ft. and 8200 ft. 

Photos 3 & 4: Small (10cm deep) wind slab failure resulting from a ski cut on a NE facing wind loaded test slope at 7400 ft. at the coordinates attached to this observation. 

Snowpack photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
50% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Snow
Air temperature trend: 
Warming
Wind Direction: 
Northwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Periods of graupel mixed with periods of sun. NW winds scouring slopes and transporting snow along the ridges.