Donner Summit Snowpack Observations

Location Name: 
Mt. Judah
Region: 
Donner Summit Area
Date and time of observation: 
Mon, 02/20/2012 - 13:30
Location Map: 
United States
39° 18' 7.4124" N, 120° 18' 59.67" W
See map: Google Maps
US


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

The melt freeze/rain crust combo with faceted grains exists in this area on NW-NE aspects.  The facets exist above and in between the 2 crusts.  On Wildflower Ridge, 7800', we were getting consistent CT failure on top of the upper crust in the moderate range with Q2 shears.  The upper slab was still soft and 4-6'' thick.  As we moved higher up to Mt. Judah N aspects were scoured with some areas scoured down to the old crust surface.  NW slopes had the most wind deposited snow from earlier this week with surface slabs up to 12''.  The crust combo and facets were present and found but were not reacitve to hand pits.  East aspects had 3-4'' of mainly soft snow on top of a well established crust layer that was several inches thick and very strong.

No signs of snow instabilities in this area.  We didn't encounter any areas with all the ingredients necessary for slab avalanches to occur.

Weather Observations
Blowing Snow: 
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: 

Small trace of new snow overnight.  Light SW winds all day with temps cooling into the afternoon.