Wednesday-Saturday

Issued: Wed, Dec 14, 2016 at 8AM

Expires: Sat, Dec 17, 2016

Above 2,500ft Moderate

1,500 to 2,500ft Moderate

Below 1,500ft Moderate

Degrees of Avalanche Danger ?

1. Low
2. Moderate
3. Considerable
4. High
5. Extreme

Avalanche Danger Rose ?

Avalanche Problems ?

Problem Details

The danger is generally moderate, meaning human-triggered avalanches are possible. However, there are going to be pockets of considerable danger on wind loaded slopes. Additionally, north aspects above treeline harbor a deep surface hoar layer that demands extra caution.

All the recent wind has loaded south through east aspects and gullies with several layers of hard wind slab. The slabs appear to be thin (less than 30cm thick) in most areas , but thin wind slabs can be quite dangerous, and can step down to deeper layers below. In steep terrain slabs may break fast and propagate wide, as well as uphill above the rider. Probe around for strong-over-weak layering, and listen for hollow sounds under your feet. These will be indications of poor snowpack structure and signal extra caution. Remember that convex slopes are particularly weak.

On North aspects, we have a patchy buried surface hoar layer in this zone, located roughly 1 meter deep. Though hard to trigger, avalanches could occur on, or step down to this layer, causing deep and wide propagation. The presence of this layer on any particular slope will be hard to confirm/deny, so assume it exists and plan accordingly.

Recent Avalanche Activity

Recent Weather

Our last snowfall was on the 7th, when 12-15″ of low-density snow piled up. Since then, strong north-northwest winds have whipped the snow around, hammering most alpine slopes.

Cold and breezy will continue Thursday and Friday. By Saturday the flow will turn more onshore, bringing light snowfall in the 3-6″ range through Sunday. Heavy snow and strong warming is likely from Monday on.

Additional Info & Media

Use standard backcountry practices to minimize your risk. This means traveling one-at-a-time through steep areas, using safe zones to stop and rest, and never traveling above your partners. Don’t commit to any slopes steeper than 30 degrees without thoroughly evaluating the snow on that slope, and making a plan for managing the danger/terrain.  Even small slides can pile up deep. Stay out of gullies, depressions, and terrain traps. ALWAYS wear a beacon, shovel, and probe and know how to use them.

Posted in Transitional Zone Forecasts.
Erik Stevens

Forecaster: Erik Stevens