Persistent slabs remain prime for human-triggered avalanches, especially at treeline.
The likelihood of triggering will increase with each day of warm weather.
Steady strong wind will continue to develop fresh, reactive slabs in leeward terrain. If triggered, wind slab avalanches may step down to deeper layers resulting in larger-than-expected avalanches.
Several recent avalanches in the region continue to be triggered on a layer of buried surface hoar or weak, sugary facets overlying a crust. Use caution in shallow areas where triggering these avalanches is most likely.
On Tuesday, large persistent slab and wind slab avalanches (up to size 2.5) occurred naturally on east slopes at treeline and alpine, respectively. Whumpfs and shooting cracks were also observed at treeline. Large avalanches continue to surprise skiers across the region, with several remotely triggered from a distance from low-angle or flat terrain.
For more information, click on the photos below.
Expect to find up to 25 cm of settled snow in wind-sheltered and shady areas. This snow covers wind-affected surfaces or a crust on sun-exposed slopes and at lower elevations. A layer of weak, faceted crystals over a crust, or surface hoar, is the primary layer of concern, buried around 40 to 80 cm.
A sun crust may have formed on the surface on steep south and west-facing slopes, and snow will be heavier and possibly moist or crusty at lower elevations.
Wednesday Night
Cloudy with 2 to 4 cm of new snow expected. 50 to 60 km/h southwest ridgetop wind. Treeline temperatures around 0 °C. Freezing level around 1000 m.
Thursday
Cloudy with 2 to 4 cm of new snow expected. 50 to 70 km/h southwest ridgetop wind. Treeline temperatures around +2 °C. Freezing level rising to 1800 m.
Friday
Mainly cloudy with no precipitation, 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around +5 °C. Freezing level rising to 2200 m.
Saturday
Mainly cloudy with no precipitation, 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around +9 °C. Freezing level rising to 3500 m.
More details can be found in the Mountain Weather Forecast.
