Mini- Morrison, Convict Lake

SNOWPACK OBSERVATION
Mini- Morrison, Convict Lake
Submission Info
Forecaster
Wednesday, April 12, 2017 - 2:45pm
Red Flags: 
Recent avalanche activity
Rapid warming
Mini- Morrison, Convict Lake 37° 34' 23.5452" N, 118° 50' 29.6052" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up under Mini-Morrison's (East Aspect) to assess snow warming on solar aspects and determine how much N-NE aspects were beginning to warm. Moderate winds (Whitecaps on the lake) at the Trailhead was not a good sign. Snow from trailhead to ~9400' Wannabe corn snow on E- SE-S-SW-NW below ~8300. Top 5 to 10 cm (Wet) over, 10 - 15 cm moist, resting on a melt freeze crust. Similar structure up to ~9400', layers a bit thicker with the exception of the surface, which was the same 10 - 15 cm wet snow transitioning to corn. However at this elevation due to the strong winds, a light surface crust was forming. After almost being blown over for the second time, decided to retreat. Obvious warming throughout. Eight degrees C at turn around point, 9400', SW aspect. Obvious wind transport in the upper elevations above 11,000' (small to moderate plums), extending down to 9700' (small). Below surprising amount of saltation by large melt/freeze grains. Like standing in front of a sandblaster at times. North and Northeast aspects of Mini-Morrison had finally begun to succumb to the heat with extensive rollerballing throughout and one small Loose - Wet release, which slid down to the underlying Melt-Freeze crust. Rollerballing extended up 10,000' with the largest below ~9500, Loose Wet initiated below ~9000'. Two rather large older debris fields noted, likely from the last storm. Debris looked to be from mid-storm cycle. 

Snowpack photos: 
Wind Transport, Mini-Morrison
Rollerballs, Mini Morrison
Loose Wet Slide, Mini-Morrison
Weather Observations
Blowing Snow: 
Yes
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
None
More detailed information about the weather: 

Moderate to strong SW winds, very gusty at times to 9400'. Snow plums noted over all alpine terrain but more confined to terrain with large southerly fetches. Temperatures well above freezing from trailhead to turnaround point.  

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