Buried Surface Hoar on Lincoln Ridge

Location Name: 
Lincoln Ridge
Region: 
Yuba Pass Area
Date and time of observation: 
Tue, 01/23/2018 - 11:00
Location Map: 
United States
39° 35' 27.744" N, 120° 29' 21.732" W
US


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

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

Snowpit data and handpits revealed some areas of buried surface hoar on sheltered open slopes and meadows in the Lincoln Ridge area. In some areas, this buried surface hoar layer looked partially collapsed and was difficult to see.  This layer was buried under Sunday night's snow about 5cm (2 in) below the current snow surface. Snowpit tests indicated this layer is very weak. Since it is just barely buried there is no slab layer sitting on top of it yet. New surface hoar had also formed on the snow surface in sheltered open areas below treeline.  Deeper in the snowpack snowpit tests showed a well-bonded snowpack consisting of crusts and consolidated snow. 

In more exposed areas near the ridgeline, we did not find evidence of buried surface hoar. We did find firm wind slabs that did not show signs of lingering instability and scoured wind-sculpted surfaces on the windward aspects.  Some minor wind transport was occurring along the ridgeline with the strongest wind gusts but little to no snow was available for transport. 

Photo 1: False color image showing small skier triggered cracking due to the surface hoar failure in an area where the 4cm of snow above the surface hoar was slightly denser. N aspect 7600 ft. 

Photo 2: Wind scoured surfaces along the ridgeline at 7800 ft. 

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Light
Precipitation: 
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: 

Some minor wind transport was occurring along the ridgeline with the strongest wind gusts but little to no snow was available for transport.