Avalanche Forecast

On Sunday, numerous natural wind slabs (size 2-3) were observed. These slabs initiated as wind slabs but scrubbed down to basal facets, gaining mass and running far.

This week, reactive wind slabs will continue to form, but concern for step-down and large natural and human-triggered deep persistent slab avalanches is at the forefront of our minds. Westerly winds redistributing surface snow in conjunction with warming temperatures continue to add load to a shallow, weak snowpack. It is uncertain when the "tipping point" for large destructive avalanches will be reached, and this uncertainty demands conservative and low-consequence terrain selection. Check out this video on incremental loading to learn more.

Please continue to send in your observations through the MIN.

A light amount of new snow accompanied by strong northwest winds continues to affect wind-exposed terrain and redistributed the surface snow into fresh wind slabs in lee areas. Below the new snow, a sun crust may be found on steep solar aspects. Below 1200 m, a rain crust exists down 20- 40 cm.

Snowpack depths are shallower than normal, and several buried weak layers have been a concern over the past few weeks. Surface hoar or crust layers in the mid-snowpack may exist in this region, but field observations suggest these mid-snowpack weaknesses are less prominent here than in areas further south.

The most concerning layer in this area is at the base of the snowpack. Large, weak facets buried in November are widespread. This layer is most likely to be problematic in steep, rocky alpine terrain, where shallower wind slab avalanches can scrub down to these basal facets.

Tuesday night

Cloudy with isolated flurries, less than 5 cm accumulation. Alpine temperatures rise to -2 C. Ridge wind northwest 45-70 km/h. Freezing level rises to 1300 m.

Wednesday

Cloudy with isolated flurries. Alpine temperatures rise to -1 C. Ridge wind northwest 40-70 km/h. Freezing level rises to 1600 m.

Thursday

A mix of sun and cloud. Alpine temperatures remain elevated around -2 C. ridge wind northwest 45-60 km/h. Freezing level 1500 m.

Friday

A mix of sun and cloud. Alpine temperatures drop to -6 C. Ridge wind northwest 25-40 km/h. Freezing level 500 m.

More details can be found in the Mountain Weather Forecast.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
• Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
• Uncertainty is best managed through conservative terrain choices at this time.