Propagation Results on Buried Surface Hoar in Andesite Meadows

Location Name: 
Andesite Meadows
Region: 
Donner Summit Area
Date and time of observation: 
Sat, 01/23/2016 - 11:55
Location Map: 
United States
39° 20' 57.8256" N, 120° 21' 32.4576" W
See map: Google Maps
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: 

General observations, ski cuts on small steep test slopes, and snowpit data did not reveal any obvious signs of instability in the upper snowpack in near and below treeline terrain. The upper snowpack consists of a mix of new snow on the surface with a rain crust underneath it and consolidated snow and rain crusts below that. Snowpit data also showed the buried surface hoar layer intact below a firm slab layer about 115-120 cm thick. Tests targeting this surface hoar layer indicated that if it does break fractures could still propagate along this persistent weak layer.

Video: Propagation Saw Test targeting the deeply buried surface hoar layer. 

Snowpit or crown profile photo or graph: 
Snowpit videos (tests, etc): 

PST 26/120 on buried Surface Hoar

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Snow
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour