Whumpfing and Unstable Test Results on Red Lake Peak

Location Name: 
Red Lake Peak
Carson Pass Area
Date and time of observation: 
Sun, 01/07/2018 - 12:30
Location Map: 
United States
38° 43' 14.1888" N, 119° 58' 26.814" W

Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain

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

Numerous signs of lingering instability existed on Red Lake Peak today. In areas where new precipitation had fallen on loose weak surface snow (near surface facets), a breakable rain crust with between 10 and 20 cm (4 to 8 inches) of new snow existed above this loose weak layer. The weak layer was moist to wet at the lower elevations (below 8500 ft.) and moist to dry at the upper elevations (above 8500 ft). It remained loose and weak at all elevations. Numerous skier triggered collapses, whumpfs, and cracking occurred on northerly aspects between 8300 ft. and 9100 ft. Snowpit tests yielded the following results: @8600 ft. ECTP on a N-NW aspect, @8880 ft. ECTP on a N aspect, @9000 ft. on a NE aspect ECTN - PST 35/100 END, and at @9100 ft. ECTN on a NW aspect.  We only traveled in lower angle terrain that was not connected to steeper slopes due to the ample evidence that the persistent weak layer remained loose and weak even in areas where it was wet. 

Strong winds were transporting snow along the ridgelines and wind-loading leeward slopes. 

Photo 1: Skier triggered cracking on a northerly aspect at ~8600 ft. where a 10 ft. x 10 ft. whumpf occurred. The weak layer was moist facets below a rain crust at the base of the new snow.

Photo 2: ECPT on a N aspect @ 8880 ft. The weak layer was moist to dry facets below a rain crust at the base of the new snow.

Video: ECTP on a northerly aspect @ 8600 ft. 

Snowpack photos: 
Snowpit videos (tests, etc): 

ECTP @ Red Lake Peak near Carson Pass on moist facets

Weather Observations
Blowing Snow: 
Cloud Cover: 
75% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Air temperature trend: 
Wind Direction: 

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