| Trigger | Natural | Remote Trigger | 0 |
| Avalanche Type | Hard Slab | Aspect | North |
| Elevation | unknown | Slope Angle | unknown |
| Crown Depth | unknown | Width | unknown |
| Vertical Run | unknown |
Avalanche: Turnagain
Location: Sunburst top of treeline
Rounding out 2016 with the last day of our Turnagain Level One, we pre-determined to stick to meadow-skipping on Sunburst after witnessing the wind event yesterday. At 2,000 feet a four inch wind slab was evident and all terrain above exhibited anti-tracks from the South to North wind of the day before. All parties who passed us to ski the upper elevations reported back very “wind-hardened” snow. Dug 8 quick pits at 2,000 West aspect and found HS depths from 75-115, all with very clear visible 3 persistent weak layers: two buried surface layers and the melt-freeze crust on the basal facets. We had one impressive CT28SC that collapsed all three layers at the same time. ECTs were consistently propagating in the low 20’s on the December 24th BSH
Avalanche Details
As a course, we noticed three new wind slab avalanches: Elevator shaft on North facing Sunburst, South facing Tincan Proper, and cross-loaded on Seattle Ridge.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observer Comments
Recent avalanches on aspects impacted by wind.
Weather
Calm day, milk bird in middle of day.
Snow surface
Slight sastrugi starting from parking lot and getting progressively stiffer until a micro 4" wind slab in pockets at 2,000 ft.
Snowpack
Poor structure with three persistent weak layers visible to the naked eye at treeline, not always consistently reactive. Didn't get to any elevations to test wind slabs.
Small windslab at 2000 ft W Sunburst right above Treeline
CT28Q1 down40,75, 105 at same time!
Melt-freeze crust with basal facet chains attached at ground level
Close up of the melt-freeze crust at 5 cms from ground that is proving reactive in tests with shallower snowpacks