Loose wet sluffs and wet snow on Castle Peak

Location Name: 
Castle Peak
Region: 
Donner Summit Area
Date and time of observation: 
Tue, 04/17/2012 - 12:30
Location Map: 
United States
39° 21' 57.2652" N, 120° 21' 25.1748" W
See map: Google Maps
US


Red Flags: 
Recent avalanche activity
Rapid warming
Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

4-10 inches of wet snow existed above a thin and quickly melting crust on the sun exposed E-SE-S-SW-W aspects on Castle Peak by noon. The least wet snow and most supportable conditions were found on previously wind scoured SW aspects; however, even in these areas the surface snow had not transitioned to corn snow and it remained wet and sticky. Ski cuts on SE-S-SW-W facing slopes triggered roller balls up to 3 ft in diameter and some small loose wet sluffs (photo above).

On more northerly aspects several inches of wet sticky snow also existed on the surface. Snowpit observations showed a deep snowpack (320cm) in which the old persistent weak layer was buried about (220cm down) with a very strong and stable snowpack above it (video above).

Snowpack photos: 
Snowpit videos (tests, etc): 

2012 04 17 Castle 028

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: