By Mark Speicher @SpicyMountainProductions
Location: Elephants Back East Bowl
Objective: Assess snow and ski a line!
When we arrived mid-day, it was raining lightly and we found 8 inches of new, wet, heavy snow spackling the ridge to our destination, Elephants Back. Despite an unfortunately high snowline, we were happy to get 8 soggy inches out of the storm to help build the base for the season. This is exactly the type of snow that sets the foundation for a great backcountry ski season.
The objective for the day was to assess the new snow conditions after the storm, and investigate how the new snow was bonding with the old snow. We went up the ridge, linking new patches of snow and weaving through the trees. The coverage, which was between 2 inches and 2 feet depending on the terrain, provided us the freedom to mostly roam where we pleased.
New snow totals near the ridge were about 26cm (10in), varying greatly depending on where the wind had deposited the snow. The windward side of the peak was scoured to rock, and the leeward sideways loaded with “creamy” new snow. Not powder skiing, but it’s November 9th people…
On the ascent, we observed a small natural wind slab avalanche that appeared to be triggered by cornice fall during the storm. New snow had filled in the crown line, but we estimated the crown to be about 6 - 12 inches deep. It’s position, directly underneath a cornice, suggested the avalanche was released naturally and the debris was clearly visible underneath the drifted snow.
Despite keeping our eyes peeled for signs of slab and loose wet activity, this small slab avalanche was the only avalanche activity we observed during our trip. We initiated a few pinwheels on steep slopes, by throwing snowballs onto the moist snow surface. Sure enough, the above freezing ambient air temperatures and significant amount of moisture in the snowpack glopped up and gained steam as the pinwheels rolled down the slope, alerting us to the potential for loose wet avalanches.
We scoped the area the day before to assess the coverage before the storm, so we had a pretty good idea of where to ride without trashing our boards. At the top of the small chute, the wind was loading snow into the bowl below. We threw a few more snowballs to identify the snow texture. It was different from the mushy, creamy stuff we had seen elsewhere. By smashing the snow grains apart and cramming them together on this slope, the wind had created a firm board.
Taking into account the recent wind slab and loose wet avalanche problems, we made sure our descent was not going to involve either of these avalanche problems. We eyed a line with moderate steepness and made some observations as we approached. We felt good about the wet loose problem: the snow still had time before the surface snow instability would become a serious issue. We made a few observations, including stomping on some inconsequential test rolls with the same aspect and elevation and wind loading as our line and nothing budged.
Our confidence in the snowpack for our terrain choice was high. We rode the line one at a time, and after the first few firm turns, the whole run was creamy goodness! We felt comfortable opening up our turns with some speed based on our research from the previous day. The coverage was thick and the skiing was surprisingly good!
At the bottom of the run, we dug a quick pit to get a better perspective on the underlying snowpack. We had a good idea from tracking the season’s conditions, but it was nice to dig into the snow, identify the significant layers with hand hardness and perform a couple tests. We did a Compression Test and an Extended Column Test. Our tests revealed a weak layer at the interface of the new and old snow. Our extended column test did not show potential for propagation across the new snow/old snow interface. We submitted our observations to the Sierra Avalanche Center and can be seen on 11/9/21 in the archives.
Snow Profile from a quick pit below Elephant's Back in the South Lake Tahoe Backcountry on November 9, 2021.