Buried Suface Hoar in Negro Canyon

Location Name: 
Negro Canyon
Region: 
Donner Summit Area
Date and time of observation: 
Sat, 01/09/2016 - 14:30
Location Map: 
United States
39° 20' 3.3252" N, 120° 17' 52.8648" W
See map: Google Maps
US


Red Flags: 
Recent loading by new snow, wind, or rain
Observation made by: Guide at Alpenglow Expeditions
Snowpit Observations
More detailed information about the snowpack: 

On our tour in Negro Canyon today, we were able to find both the Jan. 5th and Jan. 9th buried surface hoar layers. As the freshly buried Jan 9th layer is to shallow to be of concern currently, we focused on the Jan 5th layer. Multiple CTs yielded easy, Q2 results, and multiple ECTs showed no signs of propagation. No shooting cracks, whumphing or other signs of instability associated with this layer was observed today. 

Photo #1- Jan 5th buried surface hoar down approx 30cm. This buried SH is showing signs of decomposition and sintering, but still has partially distinct SH form, approx 3-5mm.

Photo #2- Freshly buried Jan 9th SH down approx 1" (shovel shear to show layer). This buried SH is very intact still, approx 4-6mm. 

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Calm
Precipitation: 
Snow
Air temperature trend: 
Cooling
Wind Direction: 
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

mostly clear skies gave way to light snow showers in the afternoon. Very little wind observed in below TL areas.