Winds Increasing in the Sherwins

The Hose
Submission Info
Volunteer Observer
Tuesday, March 17, 2020 - 4:00pm
Red Flags: 
Recent loading by new snow, wind, or rain
Obvious avalanche path
The Sherwins 37° 36' 35.0388" N, 118° 59' 33.1404" W
Snowpit Observations
More detailed information about the snowpack: 

Went for an afternoon lap in the Sherwins from the Mill City TH. The beacon checker at the TH did not work as we passed and a self check was necessary before we proceeded. It is a sometimes circuitous route and no easy task to follow a single skin track from the Mammoth Rock TH to the Sherwins ridgetop. Some tracks are better than others in location, pitch and lack of boot tracks running up their center. We won't skintrack in your bootpack, if you agree to not bootpack in the skintrack. The latest pandemic in this region seems to be Powder Fever and there are tracks everywhere in the Sherwins.

The new snow does seem to be settling and bonding well to the old snow surface for the most part near and below treeline in this location. For the most part the new snow is still F to F+ hard, and little to no separation within the new snow was noted in hand pits throughout our ascent. At ridgetop is a different story. Sky was overcast and winds were on the increase out of the South as we approached the ridge and light snowfall was occuring. Snow transport was occuring onto the more northerly aspects. A soft (4F to 4F+) wind slab was developing. Any cracking I observed in this new slab was isolated to my skis. The early stages of small cornices are beginning to build on the ridge between Mammoth Rock Bowl and The Hose. These small features are sensitive to a skier's weight. Attached is a photo of a small slide beneath one of these newly formed cornices that was relatively fresh and appeared to be intentionally triggered by another party. On the descent, we could get small, fast, loose sloughs to run short distances in small, steep terrain features. Solar aspects at the elevation of Mammoth Rock seemed to have been affected by the sun earlier in the day.

Both the wind slab and loose dry problems were found in predictable terrain features and we managed them through terrain choices and safe travel techniques. However, the weakness right now seems to be the shear volume of traffic in easy access terrain like the Sherwins. The Tracks and Scarcity heuristic traps may be pitfalls in decision making during this period of new snow and increased demand with the ski area closed. Remember that there are people skiing above you and below you in areas like this right now. 

Snowpack photos: 
Weather Observations
Blowing Snow: 
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
Less than 1 in. per hour
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