Mount Stephen, Mount Field and Mount Bosworth avalanche closure areas will be closed for avalanche control December 19th
More snow will add mass to the slab sitting on top of the mid-pack Nov 22 facet/crust layer and the deeper Nov 13 facet/crust layer. While the likelihood will slowly decrease, particularly below treeline, we still expect to see large avalanches occur on these layers for the next couple of days.
Ongoing precipitation continues to build storm slabs, while strong SW-W winds continue to actively redistribute snow into wind slabs in lee terrain at higher elevations. These slabs will remain reactive for the next few days.
On December 18th avalanche control was conducted on Mount Dennis and on the Sunshine access road that achieved consistent results, running on average 3/4 of the runouts and up to size 3 in both areas. Areas at ridgetop and with significant wind affect had noticeably more pronounced propagation characteristics.
Ski Hills reported explosive results up to size 2, wind slabs, on previously controlled terrain.
With the continued wind and snow over the past week, there is now a 50 -100 cm+ slab overlying the November crust / facet layers. These layers have been active this week with avalanches up to size 3.5, occasionally scrubbing to ground.
Below 2100m, a new crust has formed below the recent snow as the temperatures cool from the weekend warmup.
Treeline snowpack depths range from 100-180 cm!!
The week of consistent snowfall continues into Friday with one more system. This one will be slightly less impactful but will still have strong to extreme west ridgetop winds and 5-15 cm of snow. A cold front will move through Fri. This will bring the heavy snow to and end across the region and winds should ease. Temps will drop behind this front, but the coldest temperatures will remain to the east of the mountain parks.
