Although the recent natural avalanche cycle has ended, explosive control continues to produce large avalanches that run to mid runout. The snowpack need time to adjust to the 100-140 cm storm snow load that it has received since early December. Avoid the temptation to jump into bigger terrain, there is great skiing in the trees.
Lots of fresh snow available for transport and moderate to strong southerly winds have created fresh wind slabs in the alpine and in open terrain at treeline. Winds are forecast to continue for Sunday and will add to the slab formation.
The natural avalanche cycle on the mid-November persistent layer (now down 80-140 cm) has ended, however the snowpack needs time to adjust to the recent large load. While likelihood of avalanches will slowly decrease, we still expect large avalanches on these layers for the next couple of days.
Highway avalanche control in Yoho and Sunshine on Dec 18 and 19 produced results in the 2.5-3 range.
Lake Louise skihill reported several explosive triggered wind slabs up to 1.5.
Sunshine reported one size 3 persistent slab in previously uncontrolled terrain and one size 2.5 windslab.
There has been 5-15 cm of new snow since Friday and recent mod to strong SW winds have produced fresh wind slabs in alpine and treeline elevations. There is 35-50 cm of settled storm snow over top of the Dec 15 melt freeze crust (which rises to 2000m).
The mid Nov crust interface is down 80-140 cm and was active this week with numerous large natural and explosive controlled avalanches.
Treeline snow depths are around 100-180 cm.
Light flurries continue through Saturday night and Sunday with total accumulations along the Divide up to 10 cm. Moderate SW winds and treeline temperatures around -8C forecasted for Sunday.
Link to updated weather forecast tables from Environment Canada.
