22-23

There was a large natural avalanche that broke yesterday on Bald Peak it was bounded laterally by the terrain, so it only broke a couple of hundred feet across, but it appeared to be 4-6' deep and ran the full available vertical into the creek below. This avalanche was the key piece of information for the day and answered the question of whether or not the snowpack is continuing to produce deep slab avalanches with every storm, it is. Photo: GNFAC

There was a large natural avalanche that broke yesterday on Bald Peak it was bounded laterally by the terrain, so it only broke a few hundred feet across, but it appeared to be 4-6' deep and ran the full available vertical into the creek below. This avalanche was the key piece of information for the day and answered the question of whether or not the snowpack is continuing to produce deep slab avalanches with every storm, it is. Photo: GNFAC

There was a large natural avalanche that broke yesterday on Bald Peak it was bounded laterally by the terrain, so it only broke a couple of hundred feet across, but it appeared to be 4-6' deep and ran the full available vertical into the creek below. This avalanche was the key piece of information for the day and answered the question of whether or not the snowpack is continuing to produce deep slab avalanches with every storm, it is. Photo: GNFAC

We saw three more avalanches that broke at least a few feet deep and several storm slab avalanches that failed within the new and wind-drifted snow. Photo: GNFAC

We saw three more avalanches that broke at least a few feet deep and several storm slab avalanches that failed within the new and wind-drifted snow. Photo: GNFAC

We rode into Lionhead Ridge to pull the weather station for the season. There was a large natural avalanche that broke yesterday on Bald Peak it was bounded laterally by the terrain, so it only broke a couple of hundred feet across, but it appeared to be 4-6' deep and ran the full available vertical into the creek below. This avalanche was the key piece of information for the day and answered the question of whether or not the snowpack is continuing to produce deep slab avalanches with every storm, it is. 

After dealing with the weather station, we rode around to Denny Creek and up under LH Ridge. We saw three more avalanches that broke at least a few feet deep and several storm slab avalanches that failed within the new and wind-drifted snow. No other observed avalanches were as large as the one on Bald Peak. 

We stayed in terrain less than 30 degrees steep, with minor exceptions on small slopes. We avoided all large, wind-loaded slopes and crossed below them cautiously. The snowpack maintains the characteristics of mid-winter, and deeply buried persistent weak layers remain a concern. Going forward, we will continue to assess the upper few feet of the snowpack for instability before considering any steep slopes. We will continue to manage the deep slab avalanche problem through avoidance (of avalanche terrain) and consequence minimization (by selecting non-wind-loaded slopes that are smaller and free of terrain traps). 

Our party of 6 stayed at the Hellroaring Creek hut over the weekend. The winds and snowfall were intense, with the snow turning more graupelly by mid Saturday.
We dug a pit on a southerly aspect of Mount Nemesis, near the hut around 8000.’ We noted the complex layering, including a weak layer about 20” down that failed on the 23rd shovel hit. 

On Sunday morning the sun broke through for a bit and allowed us to view the widespread avalanche cycle that occurred overnight on all aspects. Across the creek, we saw a large crown (approx 3’ in depth) in the meadows. 

An avalanche that occurred on Nemesis’s south face ran from mid mountain all the way into Hellroaring Creek, running over our old skinner. 
 

The natural slides on Nemesis’s north face were some of the biggest we have seen in any slide, knocking out a lot of trees towards the bottom.