Avalanche Forecast

Wednesday night: Cloudy, scattered snow with up to 5 cm possible, light southwest winds, gusting at ridge-top, alpine high temperature -6 C.

Thursday: Cloudy, scattered snow with up to 5 cm possible, light variable winds, alpine high temperature -5 C.

Friday: Mostly cloudy, 5-10 cm of snow, light variable winds, alpine high temperature -4 C.

Saturday: Cloudy, 10-15 cm of snow, light north winds, alpine high temperature -3 C.

Since the weekend storm, there have been several reports of small wind slabs from human triggers, primarily on easterly aspects at upper elevations, in addition to several reports of dry loose avalanches. 

During the weekend storm, numerous size 2-3.5 avalanches released naturally in the storm snow. These avalanches primarily occurred on leeward aspects at treeline and alpine elevations. Below tree line, large wet loose avalanches ran naturally on Friday and into Saturday during the warm temperatures.

Over the past week, there have been a handful of notable natural avalanches breaking on more deeply buried weak layers. These were very large (size 3-4) avalanches releasing on slopes above 2200 m in the southeastern part of the region. Although the likelihood is decreasing, these avalanches are a reminder that a deeper instability may linger in shallow, rocky, alpine start zones where the snowpack transitions from thick to thin. Wind slab avalanches or cornice fall may have the potential to step-down to these layers. 

Ongoing snowfall since the weekend storm has totaled 20-40 cm. Human-triggered avalanches may be possible where this snow is being drifted by wind onto leeward features at upper elevations. Cornices are large and looming and may be reaching their breaking point.

30-70 cm fell during the weekend storm at upper elevations (above 1900 m). Strong winds originating from the southwest and shifting to the northwest redistributed the snow onto lee aspects near and above tree line and accelerated cornice growth. During a warming event Saturday night, rain saturated snow surfaces up to around 1900 m that have since formed a crust.

The mid and lower snowpack is generally well settled and strong. Although isolated, there are two deeper layers that may still persist. A layer surface hoar currently buried 100 to 180 cm deep from late December and a facet/crust layer from November near the ground. 

• Avoid freshly wind loaded terrain features.
• Seek out sheltered terrain where new snow hasn't been wind-affected.
• Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.