Avalanche Forecast
Regions: Northwest Inland.
Another 10-20 cm new snow will fall with moderate to strong southwest and west wind forming fresh storm and wind slabs which are likely reactive to human triggers.
Confidence
Moderate - Uncertainty is due to the track & intensity of the incoming weather system.
Weather Forecast
Thursday night: Cloudy, 5-10 cm snow, moderate southwest wind, alpine low -3 °C, freezing level around 1300 m.
Friday: Mix of sun and cloud, 5-10 cm snow, moderate to strong west wind, alpine high -2 °C, freezing level around 1000 m.
Saturday: Mix of sun and cloud, up to 5 cm snow, moderate westerly wind, alpine high -5 °C, freezing level around 800 m.
Sunday: Sunny, trace of new snow, light northeast wind, alpine high -3 °C, freezing level at 1100 m.
Avalanche Summary
On Wednesday, a large (size 2) wind slab released naturally on an east aspect in the alpine. A small (size 1) wind slab avalanche was observed in a cross-loaded feature near ridgetop.Â
A naturally triggered size 2 wind slab avalanche was reported on a steep cross-loaded alpine feature on Tuesday. Many small dry loose avalanches were observed as well.Â
Snowpack Summary
10-30 cm new snow add to the 10-40 cm of recent snow, which overlies a hard melt-freeze crust. The previous snow surface was wind affected and in some wind-exposed areas the wind had scoured the snow down to the crust.Â
Cornices are very large and exposure to them should be minimized, especially during warm or windy weather.
Terrain and Travel
- Watch for fresh storm slabs building throughout the day.
- Closely monitor how the new snow is bonding to the crust.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Avalanche Problems
Storm Slabs
10-20 cm snow fell on Thursday and another 10-20 cm are forecast by the end of the day Friday building reactive storm slabs.
At lower elevations, the precipitation might fall as rain and weaken the snowpack resulting in wet loose avalanches.
If the sun comes out, the potential for wet loose avalanches will increase, especially on steep sun-exposed slopes.
Moderate to strong southwest and west wind will redistribute the snow and form fresh wind slabs throughout the day in lee terrain features in the alpine and at treeline. Wind slabs will likely be reactive to human triggers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2