Quick report
- Cracking
- specific
Stormy day in the Crystal area. Reactivity of slabs appeared to increase throughout the morning and they were touchy by the time we exited the field around 1:00pm. Visibility was poor, so not a lot of avalanche observations from the surrounding area, but there was plenty of blowing snow, textured surfaces, drifts, cracking, and fresh cornices. We watched leeward ridgelines actively load during our time out. Windward slopes were getting scoured down to the 3/9 sun crust.
Lots of cracking in wind-loaded terrain near ridgelines.Weather
Snowing and blowing most of the morning. Hard at times.
Snowpack
The new snow was poorly bonded to the 3/9 interface which mainly was a melt-freeze crust except on Northerly slopes. There is also weakness just below the 3/9 melt-freeze crust which was highlighted using til tests, shear tests, and compression tests.
Looking at the deeper layers, the EFC failed every test I threw at it:
Deep tap tests failed suddenly [DT22, DT27]
Andy's Deep ECT propagated across the block [D-ECTP30]
Propagation Saw Tests went to the end [PST 32/100 (End) and PST 34/100 (End)]
Multiple other interfaces failed during compression tests or as blocks were pulled out of the pit wall with PSTs or others.
I briefly looked at the basal structure, and it was mediocre. I was focused on the EFC.
Avalanche
I was easily triggering small pockets on leeward slopes near ridgelines. I accidentally triggered a slab larger than a pocket when a sensitive cornice fell on the slope below. An avalanche class was in the area and they triggered a mid-slope slab in the new snow. Slabs were roughly 4" deep and mostly soft.