Castle Peak Observations

Location Name: 
Castle Peak
Region: 
Donner Summit Area
Date and time of observation: 
Tue, 04/19/2011 - 09:30
Location Map: 
United States
39° 21' 49.7412" N, 120° 20' 49.4088" W
See map: Google Maps
US


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

Trace to up to 4-5'' of storm snow from Monday.  Very wet high density snow with a rain crust forming at the end of the storm up to 8850'.  This rain crust was 1'' thick and very weak, not supportable except right on ridge tops and on higher windward aspects.  Rain runnels present on all elevations and aspects with some small point releases from yesterday-all observed on shaded aspects.  On shaded aspects the upper 1.5' of the snowpack is moist or wet and very loose, not being held together very well with the lack of a good freeze last night.  No skier triggering of any avalanches in the mid morning hours and stability tests-ECT, CT, PST- did not indicate any easy failures or propagation.  Depending on how much warming and solar radiation occurs today that could change.

 

Photo#1:  Showing recent small point releases probably from sometime during the rain event of late yesterday.  North aspects, 8700'.

Photo#2:  Rain runnels on all aspects and elevations.

Photo#3:  Showing the 4-5'' of new wet storm snow on the old snow surface.  The surface crust was 1'' thick and not ski supportive. 

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: 

Fog in town in the morning.  Mid level clouds on the Sierra Crest with a cloud ceiling of 8800'.  At 9am, air temp was .5c and Tsurf was 0c.  Mostly cloudy at these elevations with little solar radiation in the mid morning hours.