Fresh snow, Surface instabilities in the lakes basin

Red Cone, Hollywood trees
Submission Info
Monday, March 2, 2020 - 11:30pm
Red Flags: 
Recent avalanche activity
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
37° 35' 56.3748" N, 119° 1' 22.3896" W
Snowpit Observations
More detailed information about the snowpack: 

It was a very cold and breezy morning as we made our way out to Red Cone bowl in the Mammoth Lakes basin this morning. With reports of touchy wind slab development yesterday, my primary goal was to see how the shifting winds have redistributed the fresh snow as well as to evaluate current surface instabilities.

New snow totals seem to be in the 15-35cm depending on the elevation with drifts over 40 cm deep in wind drifted catchment zones. Loose-dry sloughs initiated easily on a couple steep convex test slopes along our ascent to red cone ridge and on one steep convex slope along our descent through the Hollywood trees we initiated a few more sizable loose dry avalanches.(D1-1.5) This area is  benchy complex terrain with numerous cliff bands, convex, steep slopes, and underling terrain traps. It seemed that the new snow is fairly well bonded, and Loose-dry avalanches seemed isolated to areas with very steep slope angles (~40°~+). Not signs of Storm slab instabilities were observed. 

The biggest takeaway today was the current snow transport resulting from the ENE winds. extensive flagging was visible along the crest and off of the summit of Mammoth mountain. Locally in the Red cone area exposed northerly and easterly facing terrain above treeline saw significant scouring.  Fresh loading was occurring on the NW facing terrain off the ridge, in cross loaded depressions near and above treeline, and I found a few isolated areas in convex catchment zones near and below treeline with reactive wind slabs 20-30 cm deep. 

My takeaway today was that the distribution of wind slabs will be highly variable due to the erratic nature of the strong winds that we're currently seeing with some areas which have been previously loaded now being scoured and vice versa. Typical surface clues may only tell part of the story, and localized evaluations are important.  Also, my observations today suggest wind loading occurring at the near treeline elevation may be the most consequential. Winds in the high alpine were doing some significant scouring. While I’m sure there are areas such as confined couloirs, cross-loaded gullies, and leeward slopes with just the right orientation in the alpine that would be problematic, the extensive flagging suggests a lot of sublimation is occurring at higher elevations. Relatively lower wind speeds and the more sheltered nature of the mid-elevations seemed more conducive to extensive slab development on our travels today.

Snowpack photos: 
Weather Observations
Blowing Snow: 
Cloud Cover: 
Air temperature: 
Below Freezing
Wind Speed: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 

very cold temperatures, clear skies, and strong winds at ridgetops. the wind seemed to pick up throughout the morning with strong winds present even at lower elevations around mid day.

0700 @8600' 9°F calm clear skies

0930 @10200' 8°F strong NE winds clear skies

1115@9000' 19°F moderate NE winds clear skies

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