In Storm Natural Avalanches: Mammoth Crest/Snowpack Tests Red Cone

Submission Info
Sunday, March 4, 2018 - 12:00pm
Red Flags: 
Recent loading by new snow, wind, or rain
37° 35' 53.52" N, 119° 1' 24.24" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up to the top of Red Cone to look at how the storm snow was settling and see if we could still find the facets buried underneath. The facets up there are buried down below at least 1.75m of snow in places and we never dug down that far. Storm snow depth varies between 50-60cm below 9700' and 140cm at 10,000'. The storm snow is still very soft and unconsolidated with slight changes in desity between F- and F+. The top 15cm or so of the new snow is settling with slightly slabby characteristics at all aspects and elevations. Dug a profile on a NE aspect at 10,174' with no real concerning results (see attached profile). Another quick test site around the ridge on a NW aspect had very simialr results: CTE RP down 10cm, CTM RP down 27cm, CTH BRK down 54cm, all results at minor desity changes between F-/F snow, F/F+ snow, and F+/1F snow. Other than a few hand shears that failed on isolation at the new/old snow interface or under the settling top 15cm, a few very short (2') cracks in the storm snow on steep rollovers, there were no signs of instability on our very very conservative route. Everyone on Red Cone today gave steep terrain and the Bowl iteself a wide berth.

The Crest was riddled with the remains of many D1 and D2 natural avalanches from the recent storm, as well as a few D3+ avalanches with crowns that appeared to be over 1m deep like one above TJ Bowl and a D2 avlanche in Red Cone Bowl (see photos).

Small amount of snow transporting over the Crest above McLeod Lake by 230pm from light SW winds. More blowing snow visible at the top of Mammoth Mtn. on our drive home.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
D3 Avalanche from in storm above Tj Bowl, and other smaller slides
In storm D2 in Red Cone Bowl
Weather Observations
Blowing Snow: 
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