We toured the Butler Fork zone today in BCC. Skies were cloudy (BKN) at the trailhead, with temperatures ranging from the teens to mid-20s throughout the day. There were trace amounts of precipitation (S-1) in the morning from 0630 until about 0715. There was no wind at the trailhead and occasional light winds (less than 5 mph) from the WSW above 8,500' along exposed ridgelines.

There were some small storm slab slides (3-4" deep and 20' wide) on some steeper slopes along the initial Butler Fork skintrack. They appeared to be triggered by wildlife. Hand pits had a moderate result at the old/new interface. We toured up a low-angle north facing ridgeline to approximately 8,500' where we dug a full study pit (see the "Butler Fork N Facing" pit profile). The height of snow (HS) was 170 cm. We identified a thin faceted layer (4F hardness) at approximately 100 cm and a crust at 70 cm. The persistent weak layer (PWL) was present in the bottom 40cm of the snowpack. We conducted an extended column test with no result (ECTX). We suspect the PWL was buried deeper than we could affect, thus the ECTX.

We continued our tour up the ridge and saw obvious signs of wind loading above 8,500'. Small cornices were present along the E/NE portion of the ridgeline. We dropped our first run and enjoyed some great powder turns in low-angle, north facing glade! Smiles abound! We toured up to Mt. Reynolds ridgeline where another party was transitioning to ski one of the glade runs. They triggered a collapse (no avalanche) on the initial ridge convexity as soon as they began their ski down. We dug a quick test pit (see "Reynold's Ridgeline" pit profile) in this area to see which layer the collapse occurred. Unsurprisingly, the collapse occurred in the PWL at the bottom 25 cm of the snowpack. The height of snow (HS) in this pit was 115 cm. The new snow (F hardness) overlaid a hard wind slab (1F hardness) located at 95 cm. The snow was rightside up below the windslab until you reached the PWL at 25 cm. Our extended column test resulted in crack initiation and propagation in the PWL (ECTP20). We also conducted a propagation saw test (PST) in the PWL. We were able to propagate the crack to the end after passing the saw halfway through the column (PST 50/100 END).

While our ECT in the first pit had no result (ECTX) as the weak layer is buried deeper, our second test pit shows that the PWL is still reactive in shallow snowpack. Staying aware of where the PWL lives (aspect and elevation) and the snowpack depth will continue to be part of our tour planning, execution, and debriefing process.

We wrapped up the day with some great low angle powder turns in the glades!