Avalanche Forecast

Moderate - Uncertainty is due to how buried persistent weak layers will react with the forecast incoming weather.

Saturday night: Clear with cloudy periods, trace of new snow, moderate northwest wind, alpine temperature 0 °C, above freezing layer between 1300 m and 2000 m.

Sunday: Mainly sunny with cloudy periods, trace of new snow, strong northwest wind, alpine high +1 °C, freezing level dropping from 2000 m to 1300 m. 

Monday: Mainly cloudy with sunny periods, up to 5 cm new snow, moderate northwest wind, alpine high -5 °C, freezing level at 1000 m. 

Tuesday: Mainly sunny, no precipitation, moderate to strong northeast wind, alpine high -10 °C, freezing level at 500 m. 

There have been isolated, skier reactive slab avalanches to size 1.5 on weak, feathery surface hoar crystals buried 25-50 cm at treeline and in the lower alpine. 

On Friday, a natural large slab avalanche was observed on a northeast aspect that likely released on the buried surface hoar layer. Skiers triggered small (size 1) avalanches on a northeast aspect on the same layer. 

A professional operation reported a slab avalanche being triggered by a wet loose avalanche from above on Thursday. And skiers triggered a size 1.5 slab avalanche from a distance away. It likely released on the buried surface hoar layer. 

There's a lot going on in the upper snowpack. Careful assessment is recommended. 

There is a crust on the surface at lower elevations and on solar aspects at treeline.

Feathery, weak surface hoar crystals buried around February 26th are found down 25-50 cm, most prominently at treeline elevations. There have been reports of this layer being reactive to skier traffic. 

A thick crust buried in mid-February is now found down 60-100 cm. Though there has been little avalanche activity reported on this layer, it should be treated with suspicion. 

The lower snowpack is effectively bridged by the layers above, and we do not expect avalanches to be triggered in the lower snowpack at this time. 

• Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
• Surface hoar distribution is highly variable. Avoid generalizing your observations.
• Avoid travelling on slopes below cornices.
• Firm cornices can pull back into flat terrain at ridgetop if they fail.