Crown profile near Cup Lake Peak

Location Name: 
Cup Lake Peak
Region: 
Echo Summit Area
Date and time of observation: 
Mon, 03/01/2010 - 10:45
Location Map: 
United States
38° 49' 53.292" N, 120° 5' 15.504" W
See map: Google Maps
US


Red Flags: 
Recent avalanche activity
Obvious avalanche path
Observation made by: Professional Observer
Snowpit Observations
More detailed information about the snowpack: 

Photo 1: Pit located 1 meter into crown above small trees. This crown was visible on the morning of 2/27 and likely occured naturally the night of 2/26 or very early morning of 2/27. Similar aspect and elevation to human triggered avalanche on Ralston 2/28, about 1/2 mile away. Light precip on 2/27 and winds since have deposited about 20cm on the bed surface just under the crown. Crown width 100 meters, avalanche length 300 meters

Photo 2: Graupel in the weak layer

HS 310cm

PST 30/100 END at 80cm

PST 90/100 END at 80cm

PSP 40/100 END at 80cm

ECTXs had some moderate Progressive Compression within top 25cm

Inconsistent PST results, but show propagation still possible, though ECTX tests imply initiation difficult (at 80cm, weak layer just beyond usefull depth of ECT)

Snowpit or crown profile photo or graph: 
Snowpack photos: 
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: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: