Donner Summit Observations

Location Name: 
Donner Pass
Region: 
Donner Summit Area
Date and time of observation: 
Sun, 01/17/2010 - 15:00
Location Map: 
United States
39° 18' 48.8952" N, 120° 19' 20.4636" W
See map: Google Maps
US


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

Toured around the Donner Summit area and made observations around 7400' on N and NW aspects.  The new snow/old snow interface appeared to have a good bond with the storm starting off relatively warm and cooling as we were skiing.  Dug several hand pits testing this interface with no results and also tested it with many ski cuts in small steeper convex terrain with no results.  There were moderate SW winds with good transport of new snow onto lee slopes, up to 4-8'' of new snow in wind loaded terrain at this elevation by mid afternoon.  I tested the 1/11 melt freeze crust with CT's with no results above or below this crust at this location, snow grain identification was nearly impossible today so couldn’t get a good idea if near crust facets were present or not .  Some cracking occurring around skis while skinning but no shooting cracks or other signs of propagation or instability.  Did some tilt tests with the new storm snow finding a failure early in the storm snow but all had poor shear quality-Q3.  There was a small break in the storm at 4pm, winds remained consistent. 

AirT= -2. TSurf- -3   

Any other comments about the observation or links to outside pages that have more info on the observation: 

 

Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Snow
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
Less than 1 in. per hour
More detailed information about the weather: