Avalanche Forecast

Last week through Friday, dize 1-2 wind and storm slabs were reactive in wind-loaded and ridge features at upper treeline and above with the past storms. A few loose-wet and snowballing were reported below 2000 m into the BTL.

Looking forward, we expect new storm slabs to become increasingly reactive as snowfall accumulates overnight, first in wind-loaded areas and then becoming widespread Sunday morning.

Overnight snowfall covered wind-affected snow and crust at upper elevations and moist snow and dirt at treeline and below.

Where the snowpack is growing, a weak drought layer is down 20-50 cm. This layer consists of hard, wind-affected snow in the alpine, surface hoar or facetted snow in sheltered areas, and a crust on solar aspects and on all aspects below 2200 m. Below this layer, several other facet-crust interfaces exist in the snowpack.

Terrain features poke through a building snowpack that ranges from 80-150 cm in the alpine and 50-70 cm at treeline. Below treeline is below the threshold for avalanches.

Saturday night

Heavy precipitation and extreme southwest wind will peak around midnight, then temperatures cool and winds decrease. 15-30 mm precipitation overnight, alpine high -1 C, snow/rain line peaking around 1000 m.

Sunday

Up to 30 cm new snow by morning, and convective flurries possible throughout the day. West wind decreasing to moderate, treeline temperatures dropping to -10 C, and freezing level dropping to valley bottom.

Cold and sunny, with patchy clouds. Moderate northeast wind, treeline temperatures around -12 C, and freezing level falling to valley bottom.

Cold with a mix of sun and cloud. Light to moderate southerly wind, treeline lows down to -16 C.

More details can be found in the Mountain Weather Forecast.

• Investigate the bond of the recent snow before committing to your line.
• Dial back your terrain choices if you are seeing more than 25cm of new snow.
• Be especially cautious as you transition into wind affected terrain.