Wind transport and snowpit on Castle Peak

Location Name: 
Castle Peak
Region: 
Donner Summit Area
Date and time of observation: 
Thu, 12/20/2012 - 10:50
Location Map: 
United States
39° 21' 55.548" N, 120° 21' 35.136" W
See map: Google Maps
US


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

Plenty of old snow on the ground available for wind transport along ridges. New wind slabs forming in lee areas, but fairly far down slope due to the strength of the winds.

Continued instability of older wind slabs observed in the snowpit. Dec 2 facet layer primed to fail under additional loading. The Dec 12 facet layer appears more stable at this location.

Surface hoar up to 6mm observed in open, wind protected areas well below treeline. Surface hoar showed signs of persisting until tonight's snowfall. None existed in areas with any amount of wind exposure.

Video: Wind transport over the SW ridge of Castle Peak.

Snowpit or crown profile photo or graph: 
Snowpit videos (tests, etc): 

20121220 Castle Peak wind loading.MOV

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Strong
Precipitation: 
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: 

Clear in the early morning with increasing mid and high cloud cover evident by mid day.