Persistent Weak Layer on Elephant's Hump

Location Name: 
Elephant's Hump
Region: 
Carson Pass Area
Date and time of observation: 
Sat, 01/20/2018 - 12:30
Location Map: 
United States
38° 41' 26.8872" N, 119° 58' 28.2036" W
US


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

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

Observations targeting the persistent weak layer in areas close to previous locations where it remained active before the storm still yielded unstable results. ECTP 22 at the site of an old avalanche on a NE aspect near 8300 ft; ECTP 22 and 24 on a N aspect at 8500 ft, and two 2m ECTP's all indicated that this layer remains weak and that if it were to break a fracture could propagate through the layer. In other areas, tests showed that fracture propagation was unlikely (ECTN on a N aspect at 8800 ft). These mixed results indicate a degree of uncertainty about where this layer may still be problematic and where it may not. The data also indicates that this layer has become stubborn and actually trigging an avalanche on this layer may be difficult to do. The snow above this layer is a mix of thick frozen rain crusts and firm well-consolidated snow that would be a destructive slab layer if it were to slide downhill. On top of the snowpack, rested the recent storm snow which remains cold and soft. Observations did not reveal any other signs of instability. 

Snowpit videos (tests, etc): 

2m ECTP failing on a persistent weak layer on Elephant's Hump - Carson Pass - Tahoe Area

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
Clear
Air temperature: 
Below Freezing
Wind Speed: 
Calm
Air temperature trend: 
Static