Smiley Ck

We went out to look more closely at lingering and recently developed wind slabs (due to a shift in wind direction last night). We found little evidence of reactive wind slabs where we toured and glassed today. Most surface snow has been beaten-up enough over the past few days of high-pressure to resist being blown around, and we found no fresh wind slab development.

We found widespread breakable sun crusts on slopes that got baked in direct sunlight and warm temperatures earlier this week. We also found weak sugary snow in the valley bottoms, where temperatures have been extra chilly at night recently.

No obvious signs of instability observed today.

Wind slabs: We found widespread evidence of wind affected snow surfaces in most open areas, especially in the alpine and on ridgelines. Despite the appearance, much of this turned out to be thin wind-skins or old well-bonded old wind slabs. Cracking was limited to ~6 inches from our ski tips today.

Cornices: Most ridgelines are guarded with large thick cornices. Although these seemed fairly unreactive to stomping in our small test slopes today, we'd still give them a wide berth in steep terrain. Cornice-fall has been the primary trigger of recent large avalanches observed over the past week.

Slopes facing the sun: We observed 1-2cm thick (breakable) sun crusts on the surface on all SE, S, SW and W aspects. These were probably formed earlier this week and didn't break down or moisten much at all today.

Slopes facing away from the sun: We found soft supportable recycled powder overlying the 1/1 interface buried ↓40cm. At lower elevations (up to ~7500'), where colder air has been pooling overnight, we found widespread faceting of the surface snow.

*We dug one quick pit at 9000' on a N aspect that had been previously wind-loaded with a total depth of 185cm. We observed hard failures at the 1/1 interface (small grained facets) with no propagation in testing (ECTN24 @ 145cm) and the early December weak snow was buried ↓150cm.