Pinwheels, Wet Snow, and Frozen Crusts on Castle Peak

Location Name: 
Castle Peak
Region: 
Donner Summit Area
Date and time of observation: 
Thu, 03/06/2014 - 11:30
Location Map: 
United States
39° 21' 36.3168" N, 120° 21' 49.554" W
See map: Google Maps
US



Observation made by: Forecaster
Snowpit Observations
More detailed information about the snowpack: 

Photo 1: Runnels indicating free water in the snowpack

Photo 2: Ski width wide wet snow sluff triggered with a ski cut on a ESE aspect @ 7800 ft.

Photo 3 and Video: Large pinwheels triggered by a small cornice drop onto a SE aspect at 7960 ft.

Photo 4: Freezing rain on a tree at 7800 ft. Snow line was at 8700 ft. last night in this area. Below that elevation the precip fell mostly as rain. It looked like some freezing rain fell at the end of the precipitation adding a thin layer of ice to the surface.

Photo 5: A freezing rain crust on N-NE aspects. This rain crust remained hard and frozen on the northerly aspects above 8000 ft. Below this crust 6-8 inches of wet snow still existed on these aspects. Tests on wind loaded slopes indicated that the wet snow continues to consolidate and refreeze. No signs of instabilities were noted on thse aspects. On the northerly aspects below 8000 ft. the crust was more variable and sometimes it was breakable and sometimes supportable.

Snowpack photos: 
Snowpit videos (tests, etc): 

VID 20140306 103821

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Cooling
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: 

Partly cloudy skies and windy.