Avalanche Forecast

Thursday night: Cloudy, 5-10 cm of snow, light southwest wind, freezing level dropping to 900 m, treeline temperatures reach -3 C.

Friday: Cloudy, 5-10 cm of new snow, light southwest wind, freezing level climbing to 1200 m in the afternoon, treeline temperatures reach 0 C.

Saturday: Cloudy, 20-30 cm of new snow, moderate southwest wind increasing to strong in the afternoon, freezing level climbing to 1400 m in the afternoon, treeline temperatures reach 0 C.

Sunday: Mostly cloudy, 15-20 cm of new snow, moderate southwest wind increasing to strong in the late afternoon, freezing level climbing to 1300 m in the afternoon, treeline temperatures reach 0 C. 

Slab avalanches are a concern on slopes with accumulations of new snow, especially in wind-loaded terrain. No recent avalanches have been reported, but mountain travel and field observations have been very limited over the past few days.

The next low pressure system moves in overnight. 10-20 cm may accumulate by Friday afternoon at upper elevations. The new snow has the potential to form a new storm slab problem on steep slopes, especially where it has been drifted by wind. 15-25 cm of snow from earlier in the week covers a variety of snow surfaces including crusts, warm snow, and wind-affected snow. There is some uncertainty about how well the new snow has bonded to these interfaces. The snowpack is well-settled. Snowpack depths diminish rapidly with elevation, with 300-400 cm at treeline and no snow below 700 m.

• Storm slab size and sensitivity to triggering will likely increase through the day.