Mammoth Area - Lakes Basin- snow conditions

mammoth lakes basin
Submission Info
Monday, January 27, 2020 - 12:30pm
37° 37' 21.6768" N, 119° 2' 2.0364" W
Snowpit Observations
More detailed information about the snowpack: 

37F @ 10600ft @ 1200pm

46F @ 8600ft @ 200pm

I wanted primarily to get a good idea of what transpired overnight and potentially today with westerly winds and the light snowfall the range received yesterday. What better place than Mammoth Mountain to get a 360 view of the surrounding Sierra and survey all aspects. It was a bit breezy in the morning hours with moderate winds from the west, but in the afternoon, as soon as you dropped off the mountain top, light winds were 10-15mph max.

Northerly aspects in the mammoth lakes basin backcountry today harbored shallow (3-5") surface slabs, which although reactive, were very thin, and were isolated to walls of gullies or other catchment zones adjacent to rocks and cliff bands. There was a few Northerly aspects where deposits were deeper, upwards of 12" adjacent to ridgeline, but neither had much volume nor size to produce anything significant in terms of avalanche. Nothing propagated very far, nor slid any significant distance.  The majority of new snow on northerly alpine areas was not reactive at all and was fairly well pasted and bonded to old surfaces.  New snow residing at and below tree line was well pasted and there was ever so slight sloughing in really steep terrain.   Cross loaded pillows on Southerly aspects moved the most for me as they were reactive and would move down slope on the previous sun affected surfaces. Again, there was not much volume to the new snow pillows anywhere and nothing slid more than 20-30ft. The intense sun today and solar input really cooked the sunny aspects down today. Even with projected SW winds picking up again tomorrow, don’t’ believe there will be much snow to transport after today’s warmth and solar and continuing similar weather conditions for the next few days.

Lower elevations and snow exposed to the sun was incredibly sticky and wet already by noon and at 8500ft it was 46F at 200pm. It was hot, and certainly did not feel like winter.

Did not observe any recent avalanche activity on my drive along the 395 from Bishop to Mammoth.

Snowpack photos: 
Snowpit videos (tests, etc): 
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