Quick report
- Cracking
- widespread
- Collapsing
- Observed
• Can confirm the previously reported avalanche activity in Shed 7 West that ran the night of Jan. 17th. There were multiple soft slab crowns that failed in the storm snow, one nearing D2 size. • A very small, D1 soft slab ran the night of Jan. 17th in Umbrella Fence with debris burying a few wires in the slide fence • The avalanche in Shed 9 that ran sometime on Jan. 10th or 11th was a hard slab that failed on a layer of facets resting on top the late-Dec. crust (crown profile below) HS-N-R2-D2-O. o The crown ranged from 20-40” thick and was about 100 yards wide. o The slope angle where we dug into the crown was only about 30°. o It was difficult to tell how far the debris ran, but it appeared much of the mass only made it 500-700 vertical feet down slope before it was caught up in small trees. • Starting to develop a clearer picture of the general snowpack structure across the Program’s terrain. o Below 5500-6000’, where there was little to no snow before the New Year, there is a layer of depth hoar at the base of the snowpack that has been buried by 2-3’ of snow from the January storms. Ski penetration is often still to the ground. o Above 6000’, where a more developed snowpack exists, the 2-4’ of snow from the January storms is resting on top of a weak layer of facets that rests on top of a stout melt-freeze crust from late-December. • Both weak layers are producing audible collapses and shooting cracks. I lost count of the number of audible collapses, but I have not experienced that many in one day for quite some time. • We did not trigger any avalanches on test slopes or from safe ridgelines that we traveled on.
Weather
- Cloud Cover
- broken
- Wind Loading
- previous
- Recent Snowfall
- 1
- Snow Avail For Transport
- large amounts
• Broken or obscured skies above 6000’. Intermittent very light snowfall with trace accumulation by the end of the day. • Winds were calm on the Canyon floor and light from the SW above 6000’. • Inverted air temperatures and we were peeling layers as we climbed higher. Daytime high temperatures warmed to the high-20s °F above 6000’ but only reached about 10 °F on the Canyon floor.
Avalanche
Avalanches were previously reported. But learned more details today