Rain and wet snow on Andesite Ridge

Location Name: 
Andesite Ridge
Region: 
Donner Summit Area
Date and time of observation: 
Thu, 01/26/2012 - 10:15
Location Map: 
United States
39° 21' 0.4644" N, 120° 21' 47.0808" W
See map: Google Maps
US


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

Moderate rain all through the morning hours, well exceeding the forecast of 0.02" for today. Rain was noted up to the top of the ridge and the highest elevation traveled of 8,200'. The top 15cm of the snowpack was saturated from rain. The snowpack below remained wet from the warming of the past several days.

Ski cutting of test slopes produced very small loose wet snow avalanches with no propagation. Failure would initiate in the rain saturated snow and then entrain more of the deeper recent storm snow as seen in the video.

Photo 1: Rain runnels forming at 8,100'.

Photo 2: Typical test slope results

Snowpack photos: 
Snowpit videos (tests, etc): 

20120126 Andesite Ridge 001.MOV

Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Rain
Air temperature trend: 
Static
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: