June Mountain to Mammoth Mountain via San Joaquin Ridge -Snow conditions

San Joaquin Ridge-East Side
Submission Info
Saturday, January 18, 2020 - 11:30am
San Joaquin Ridge 37° 42' 49.8096" N, 119° 6' 1.4868" W
Snowpit Observations
More detailed information about the snowpack: 

Toured from June Mtn to Mammoth Mtn today to check out a variety of aspects, elevations and terrain features. It was a grey day and relatively warm with light to moderate SW winds in the morning and becoming nearly dead calm in the afternoon.  It was in the 20’sF at 11600ft mid-morning,  but upon descending down to the 8500ft level around 130pm it was very warm 44degF and the snow down there was getting very damp and gloppy.

The flat light didn’t help visually hunting for avalanches in the Ritter/Banner/Minarets range, but throughout the day I didn’t see any major slides. In the San Joaquin Ridge area I identified one class 1 avalanche that had slid on a NE aspect from tree line and ran 100ft or so. There was also some evidence of cornice drops and a small slab that had released under the larger cornice line right at Deadman Pass on the San Joaquin ridge on a E aspect.   There was no evidence of any avalanche activity failing on deeper rain crust etc. in the snowpack.

I traveled on virtually every aspect today, hunting instabilities and couldn’t find any. I ski cut wind-loaded northerly pockets, stomped on small cornice lines and dug many handpits with un-alarming results. Settlement, lack of wind, and warm temperatures are helping the new snow bond quite well and stay in place thus far.

On hand pits at 11,200ft East aspect, 39deg slope; I was able to pull cohesive blocks in a moderate fashion, but the new snow was bonded to the old firm surface, leaving a residue of the new bonded snow when you pulled the surface block off. It was F+ in nature.

The firmest wind slab that I discovered was actually on a cross-loaded SE slope at Tree line and it felt drummy and hollow. Although I couldn’t get it to move- a firmer 1F (20cm) slab was found on top of softer non- wind-effected new snow that was sitting on top of a temperature/sun crust above the Deadman pass bowl. This reminded me of potentially similar conditions on White Wing which I had observed yesterday a class 1.5 slab avalanche on a SE-E aspect below tree line that had happened mid-storm the night of the 16/17th.

I did not see any shooting cracks, feel any collapse of the snowpack and could not get anything to propagate today or remotely move down slope. No active avalanche activity today. Although grey, it was a spectacular day and a nice rest bit from the wind… watching the setting sun over the Minarets was a good reminder of the special place here in the Eastside.


Snowpack photos: 
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