Toured up into the Broken Top bowl via Ball Butte and skied A la Mode

Quick report

It was a gorgeous day in the alpine with blue skies and light winds until high clouds a a cooler breeze moved in during the afternoon. We went out to assess conditions in the high terrain with the wind slab problem and lingering instabilities on our mind. The wind effect from this weeks storms were immediately obvious throughout exposed terrain with pillowy wind drifted surfaces on leeward and cross loaded slopes (N-SE). Sastrugi, packed powder and wind stripping was observed on windward aspects (W-SW). Below tree-line there was still soft protected settled powder that made for fantastic turns in the morning. Overall, there was good snow to be found around the compass. As far as instability goes, we did not observe any obvious signs like shooting cracks, collapsing, or reactivity on test slopes. We did dig down about a meter on the SW facing apron below A la Mode and found a pretty wind packed upper snowpack with mostly 1f hardness snow throughout. However we did find the layer of weaker precipitation particles about 45cms down that has been talked about in the forecast. This layer failed at CT24 Q2 and had a progressive collapse but did not propagate in an ECTN24. The more surprising find was how quickly the snowpack changed as we ascended A la Mode. Despite more than a meter of wind battered precipitation particles in the apron, there was a stout crust with far less snow on top once we entered the choke. In some areas it was stripped all the way to the crust and in most of the couloir there was 4-18” of wind packed snow on top. We ultimately turned around before the top because hand pits and hand shears revealed a 2-5cm layer of sugary faceted snow between the 4f wind slab and the pencil/knife hard crust. This slab failed with moderate to hard force, but the structure was not good! I was not expecting to find persistent grains that high in the alpine, but they were right there on top of the crust with a wind slab atop. Spooky! Lastly, the sun was out in force so solar aspects saw some warming with occasional small rolling balls and rime shedding off cliffs. It wasn’t enough for wet problems to be an issue but I imagine there will be some degree of a thin sun crust on true solar slopes.