Hoping this finds Everyone keeping well.
It was a brilliant day to be in the mountains. Strong winds at ridgetop elevations were moving snow onto lee aspects from, at least, midday onward. The clouds never really cleared lee of the Coast Mountain crest (east of the Blowdown Creek area).
I didn't observe any new natural avalanches today but there was one impressive previously explosive-controlled slab avalanche on Blowdown Peak that dug deep into early-season layering and propagated widely in a west-northwest, steep, and rocky start zone. Without a doubt, this slide travelled quite some distance.
The January 4th 'surface-hoar' (a weak snow crystal) is buried approximately 50-60cm, from the surface, in open below-treeline locations. This layer of 'surface-hoar' is still quite evident in the snowpack and is continuing to be monitored by professionals who currently have low confidence in the strength of this layer. The mid-January crust, that is quite thick around the immediate Whistler area, is quite thin near the Coastal Divide. This crust is down approximately 5-8cm below-treeline and disappears as you reach treeline elevations.
In exposed (open) treeline locations, the recent winds have made the snow surface 'slabby'. Both harder and softer slabs exist in alpine-like terrain at treeline as well as above. Sheltered east-facing treeline locations today had the best snow and skiing quality.
The cornices above Darkside Lake (head of Steep Creek) are absolutely huge. Be cautious if you find yourself traveling below slopes that are exposed to these major hazards/potential avalanche triggers.
The crust was supportive and carried nicely on skis all the way out along the logging road to the highway.
Wishing you all safe ski-touring and a good end to January.
Best regards,
Dale Marcoux
ACMG Ski Guide