Sensitive wind slab at Carson Pass

Location Name: 
Frog Lake Ridge
Region: 
Carson Pass Area
Date and time of observation: 
Wed, 03/06/2013 - 15:00
Location Map: 
United States
38° 41' 25.9404" N, 119° 59' 10.4136" 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
Obvious avalanche path
Observation made by: Professional Observer
Snowpit Observations
More detailed information about the snowpack: 

Shallow wind slabs were widespread and easy to trigger along Frog Lake Ridge today. Winds appeared to be increasing in the afternoon, with continued wind slab formation late in the day.

Pic 1: One of many test slopes to fail at the wind slab/storm snow interface.

Pic 2: A shooting crack that when exposed with my shovel (pic 3) showed the potential to step down to the storm snow/recent MFcr interface- similar to video step-down.

Video: A D1R2 intentional trigger that began under the wind slab and stepped down to the storm snow/recent MFcr interface. To clarify my comment about the facets - they did exist at one specific point just under the bed surface, but I could not find them elsewhere under the bed surface. The weak layer was light storm snow just on top of the subtle MFcr from warm temps just prior to this storm.

Nearby, evidence of 2 natural D1 avalanches were observed, with several inches of new snow deposition on the bed surface and debris piles.

Some very early stage faceting was observed under the recent, subtle MFcr on steep shaded aspects (small, angular sugary grains that could still be pressed together). I did not observe this layer to be reactive to ski cuts, nor to D1 debris loads.

Snowpack photos: 
Snowpit videos (tests, etc): 

2013.03.06 15:00 SSAScD1R2I

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Snow
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: 

Moderate winds with strong gusts, increasing in the afternoon.