Castle Peak observations

We toured NW Castle Peak this morning to assess the upper portion of the snowpack ahead of the incoming storm. Air temperatures were below average and stayed that way through our midday departure. Generally increasing cloud cover was occurring with occasional sun breaks and occasional snow showers. Winds were light to moderate speed out of the SW, most prominent over the upper elevations.

We stopped off on a NNE aspect at 8,250' on our way up the SW ridge of Castle and dug a quick test pit looking at the recent new snow and the upper rain crust. Recent new snow was bonding well to the rain crust. There were no signs of problematic faceting below the crust in this location. Small surface hoar (January 24 layer) was buried within the recent new snow and produced very repeatable shears, but the overlying new snow was still too lacking in slab characteristics to present much of a problem just yet.

Upon making our way up to the top of the NW trees on Castle Peak we looked over the ridgetop into the terrain on the N-NE side of the peak. We could see drifting snow moving over minor cornices features and depositing as wind slab on the slope below. In this same area, we saw two ski tracks either from early this morning or from yesterday descending to the NE. One of the skiers had trigged a wind slab avalanche that was about 30' wide and ran 40' downslope, covering the upper part of their ski track. The crown appeared mostly 1 foot deep, possibly up to 2 feet deep at one end. While we were there the lighting was so poor that we were unable to capture a photo of any value.

New snow on the surface from the last 24 hours was widespread large plates and stellar snow crystals that looked like surface hoar at a cursory glance but wasn't. This was widespread over all areas traveled. Actual new surface hoar that formed last night was only seen in one isolated location north of Andesite Peak along the ridge connecting to Castle Pass. On the snow surface, the new surface hoar at 10-15mm in size was already knocked over by the wind. Only on nearby trees did we see the new surface hoar still upright.