Red Lake Peak Observation

We went to Red Lake Peak to determine the failure layer in the avalanche reported yesterday, 3/24. Avalanche Observation is available here: https://www.sierraavalanchecenter.org/observation/2023/mar/24/0900/red-l....

Despite the below-average temperatures, the strong March sunshine was warm at the trailhead around 10:30 am. As we began hiking, we experienced variable conditions with 3-4" of cold unconsolidated snow in the shade and sun crusts on solar aspects. A test slope in near treeline terrain produced a small cornice failure but no subsequent wind slab instabilities. When we got into above treeline terrain, we dug a quick pit in similar terrain to yesterday's avalanche and performed an ECT looking to identify weak layers. This pit produced an ECTN and revealed multiple graupel layers in the upper 35cm of the snowpack. As we continued up the ridge to Red Lake Peak, wind effects from both the SW and NE were evident, and ridge tops held a mix of bare ground, ice, and wind-affected snow. Winds in exposed terrain were intermittent and light to moderate throughout our tour. Snow conditions descending from the summit to the saddle of yesterday's avalanche were surprisingly good on a wind-compacted layer on a lower-angle slope. Steep terrain and remnant hangfire made annalizing yesterday's crown challenging. We were able to make safe access on a shoulder from the saddle to dig a pit. The wind slab failed on a buried graupel layer with firm snow below it (see pit). This layer was still very reactive and produced an ECTP3. We exited via the ridge and descended low-angle slope on variable but enjoyable snow. Sheltered N-aspects were holding upwards of 6-8" of cold s now, and solar aspects were warming but not to the extent of any wet slab instabilities.