Castle Peak Observations

Location Name: 
Castle Peak
Region: 
Donner Summit Area
Date and time of observation: 
Tue, 04/06/2010 - 12:00
Location Map: 
United States
39° 21' 47.1708" N, 120° 20' 28.752" W
US


Red Flags: 
Obvious avalanche path

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

NE winds in the morning were barely in the moderate range and moving snow, winds tapered off as the day progressed.  Cornices down low were fragile and were easy to kick off, none of which resulted in any propagation on the slope below.  In exposed areas corninces were firmed up by the NE winds.  We experienced some very localized cracking just below the ridgeline, not widespread and except for this one spot could not find anything similiar elsewhere.  Did some stability tests on a N aspect 8500', had consistent CT moderates with Q2 shears down 12'' from the surface.  This was at a density change within the storm snow and could be easily felt with a ski pole probe or even while skinning.  2 ECT did not propagate across the column but did have partial block failure, again down about 12''.  HS at this location was > 390cm, snow from the last 2 storms was 150cm and was good going from fist to 4F to 1F to the old melt freeze crust except for the density change at around 12'' down. 

Tested and skied many steep slopes with heavy sluffing as the main result.  Watched as snowmachiners did a good job of testing many slopes, sometimes multiples at a time with large airs off of the cornices.  No evidence of any instability.  We didn't spend a lot of time on the solar aspects but did see some small roller balls and a few small point releases coming down off of rocks as they heated up throughout the day.     

Snowpack photos: 
Snowpit videos (tests, etc): 

ECTN @ 43cm down

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