Layer Cake of Facets

Location Name: 
Strong over Weak
Region: 
Williams Lake Area
Date and time of observation: 
Tue, 01/28/2020 - 14:00



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

Went for a tour up the Williams Lake drainage. 2-4" of snow had fallen overnight. This new snow fell on various layers, from breakable crusts to harder slabs. On steep east facing slopes at mid and upper elevations, loose snow avalanches had run from beneath cliff bands. Moderate northern post storm winds impacted open areas at higher elevations. Windward northern slopes at upper elevations were scoured, and sastrugi was observed on north and east aspects near and above treeline. We did not find signs of wind slab formation. Western slopes remained stripped, with subtle signs of recent cross-loading in gullies above treeline.

On our northern aspects above treeline, we found a poor overall snowpack structure. Multiple facet layers underlay various harder slabs. See Video. One one location, we found up to seven facet-slab combos. These persistent weak layers were found throughout the snowpack. In long column tests, facet layers consistently failed and easily propagated.         

Photo 1: 2-4" of new snow improved skiing conditions.

Photo 2: Numerous facet-slab sandwiches.  

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

A cold, calm day. Winds were light, with an occasional gust in the low 20's. No day time precip.