Watch for wind loading in the alpine. Travel has improved over the past week, but the unpredictable nature of the weak snow at the bottom of the snowpack inspires little confidence. Continue to treat large steep features with caution!
The days are short and temps are dropping. Bring gear to deal with any unexpected delays.
New snow and SW winds have created small wind slabs in the alpine over the past few days. Watch for wind loading above you as these have potential for both natural and human triggering. If triggered, these wind slabs could step down to the deep persistent layer at the bottom of the snowpack.
The bottom layers of the snowpack are facetted and weak in most areas. Human triggering remains possible and this could result in a large avalanche. Given the unpredictable nature of this problem, use caution when venturing on to any steeper slope with consequence.
A few new size 1-1.5 natural wind slabs and loose dry avalanches in steep lee alpine terrain were observed on Saturday.
Whumpfing is still being reported from alpine areas (Dolomite Circuit, Hector shoulder). We suspect this is occurring on the weak basal layer.
Ski hill snow safety teams reported a few size 1-1.5 wind slabs as a result of explosives and ski-cutting work in alpine features.
5-10 cm of new snow at tree line with moderate SW winds are creating new wind slabs in alpine and exposed treeline terrain. Low elevations have a crust of refrozen snow. 15-50 cm of snow sits over the Dec 5 rain crust that exists as high as 2300 m, and is more prevalent in the southern part of the forecast area. The base of the snowpack is a mix of weak basal facets and a spotty crust from late Oct. Treeline snow depths range from 50-95 cm. Many early-season hazards still exist.
An upper ridge will bring mainly clear skies to the Alberta Rockies. West to southwest winds at ridgetop will increase through the day bringing moderate to strong winds by the afternoon. Temperatures drop tonight with alpine lows reaching -20°C overnight and highs between -10 and -5°C with a possible inversion in the alpine.
For more information, click Mountain Weather Forecast.
