Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Recent windslab formation has been extensive, and stubborn slabs could extend into openings below treeline.
Strong winds have left slabs in open features. Persistent slabs sitting on a weak layer of surface hoar continue to be most reactive at treeline and below.
Recent windslab formation has been extensive, and stubborn slabs could extend into openings below treeline.
Be aware of the potential for remote triggering and large avalanches due to buried surface hoar, especially at treeline and below. Watch for wet avalanches with sun and daytime warming, these could trigger the weak layer below.
On Saturday, evidence of a widespread avalanche cycle with avalanche to size 3 was reported, avalanches failed both within the recent storm snow and on persistant weak layers. Many avalanches were in steep open features; however, this MIN from Silent Pass reports a size 2.5 avalanche, failing on surface hoar and burying the access road below treeline.
Reactive surface hoar continues to be responsible for numerous natural, remote, and rider-triggered avalanches.
Strong westerlies have impacted 20 to 40 cm of recent storm snow, pressing surfaces and depositing slabs in lee features, including open areas below treeline. Solar slopes may become moist with daytime heating.
A reactive layer of surface hoar is now buried 50 to 70 cm deep. Recent persistent slab avalanches have failed on this layer of well-preserved surface hoar, many triggered in sheltered openings at treeline and below.
The mid and lower snowpack are well settled in some areas. In others, large facets (depth hoar) are present at the bottom of the snowpack.
Sunday Night
Clear skies. 40 km/h west ridgetop wind. Treeline temperature -3 °C.
Monday
Sunny. 50 km/h west ridgetop wind. Treeline temperature -2 °C.
Tuesday
Mostly sunny. 1 to 4 cm of snow. 50 km/h west ridgetop wind. Treeline temperature -1 °C.
Wednesday
Mix of sun and clouds. 2 to 3 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -3 °C.
More details can be found in the Mountain Weather Forecast.