Wind Slabs, Blowing Snow, and Storm Snow on Castle Peak

Driving up to Castle we could see signs of wind-loading along the highway in the form of cornices and blowing snow. At the Castle Peak trailhead, we found 18 to 24 inches of new snow. Breaking trail we could feel layers and changes in the storm snow but did not see many slab characteristics in sheltered areas. We found some small steep test slopes. When we cut these slopes, we could get the new snow to sluff on these slopes, but we did not trigger shooting cracks on these sheltered test slopes. 

We continued up into more exposed terrain along the west ridge where we could see blowing snow and cornices. These cornices were fragile and broke easily with ski kicks. On most of these test slopes, the cornice pieces would entrain the recent snow on the slopes below as a sluff. On some of the test slopes, the cornice pieces did trigger wind slab failures with wind slabs ranging from 6 inches to 18 inches deep. These test slopes failed within the recent snow above the old crusts. Most of these wind slabs did not propagate very wide across the test slopes. One of the 6 inch deep fractures did travel about 20 ft across the slope. We found the deepest wind slabs at the higher elevations and in the most wind-exposed areas as expected. When we reached our high point on the ridge, we looked over into the steeper more exposed terrain of the north side of Castle Peak. We could see large cornices along the ridge but blowing snow and clouds obscured our view of the slopes in the bowl. 

Descending back to Round Valley we ski cut a few more steep sheltered test slopes and triggered some more sluffing but no storm slabs. We saw what looked like a small storm slab fracture on a small test slope that may have been triggered by snow falling off a tree yesterday. We dug into this test slope and found that the failure layer was within the new snow.