Conservative terrain travel is recommended, as the storm snow may need some time to bond to the snowpack.
Stormy conditions since the weekend have formed storm and wind slabs that have been reactive to human traffic. These slabs may take some time to bond to underlying layers. Best to give the snow time to settle before entering consequential terrain.
Small to large (size 1 to 2) storm slab avalanches were triggered by riders, explosives, and naturally over the past couple days, generally being about 30 cm thick and primarily at alpine and treeline elevations. Some of them were triggered by small pieces of cornices failing.
We anticipate similar avalanches could be triggered by riders on Wednesday. Brief periods of sunny skies could also trigger small loose wet avalanches out of steep, rocky terrain on sun-exposed slopes.
Around 5 to 10 cm of snow over the course of Wednesday will build on the 40 to 50 cm of snow that accumulated since the start of last weekend. The wind has been consistently strong from the south to southeast, likely forming wind slabs in lee terrain features on northerly slopes.
All this snow may sit on a weak layer of surface hoar crystals on sheltered and shaded treeline and alpine slopes. The snow overlies a hard melt-freeze crust on sun-exposed slopes and on all aspects below 1500 m.
The remainder of the snowpack is well-bonded.
Cornices are large and looming and continue to grow during this stormy weather.
Tuesday Night
Cloudy with snowfall, accumulation 2 to 5 cm, 20 to 40 km/h southeast wind, treeline temperature -7 °C.
Wednesday
Cloudy with snowfall, accumulation 2 to 5 cm, 20 to 40 km/h south wind, treeline temperature -7 °C, freezing level 1200 m.
ThursdayPartly cloudy with isolated flurries, 10 to 20 km/h south wind, treeline temperature -6 °C, freezing level 1400 m.
FridayCloudy with snowfall, accumulation 5 cm, 20 to 40 km/h south wind, treeline temperature -5 °C, freezing level 1500 m.
More details can be found in the Mountain Weather Forecast.
