High spatial variability at Carson Pass

Location Name: 
Meiss Ridge
Region: 
Carson Pass Area
Date and time of observation: 
Wed, 02/20/2013 - 12:00
Location Map: 
United States
38° 42' 30.8232" N, 120° 0' 52.3332" W
US


Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain

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

Highly variable storm snow deposition and wind re-distribution, which rests on top of mostly strong crusts without associated faceting - with one observed exception.

Pics 1 and 2: At 8900ft on a NE aspect. Mid and low on this slope held patchy storm snow, with several places showing scoured crust at the surface. However, the steeper start zone held enough continuous slab to be of concern. 2x ECTN did not show propagation potential, but did show similar stratigraphy to that observed on SW aspect in video 1. Only 1 faceted layer observed at this location, just under the most recent surface crust. 2x PST 100/100 end down 60cm on this faceted layer, which was clearly rounding. I traversed well under the start zone here, and probing did not reveal any weaker faceted layers.

Video 1: At 8900ft a steep SW aspect held more storm snow and wind redistributed snow than expected. Although ski pen here was minimal, after triggering pictured shooting crack and removing skis, boot pen was to the underlying crust at 90cm deep. 2x CTV and 2x ECTPV with a distinct Sudden Collapse on low density storm snow just above previous surface crust. No persistent grain types observed here.

Video 2: At 8400ft on a NW aspect, near treeline test slope. Although PSTs did not show propagation potential, the facets just under the most recent surface crust were very well developed and quite weak.

 

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Air temperature: 
Below Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Static
Wind Direction: 
East
Accumulation rate: 
None
More detailed information about the weather: 

Tall and dark thunderheads building over Carson Spur upon my departure at 3:30pm.