[MCR] Lake Louise to Wapta Icefield Area Conditions April 2-8

[Public Mountain Conditions Report]

MCR – Rockies April 2 – 8
 
The ACMG assistant ski guide exam took place in the Rockies April 2-8. Here is what we found.
Groups skied Cirque Peak, Crowfoot Peak, Pope’s Peak, and the Wapta (Balfour, Sherbrooke, Peyto and Bow areas).
The week began with unsettled weather, moderate to strong SW winds, unseasonably cool temps between -11 and -5 at treelinewithout significant daytime warming. Snow accumulations were around 30cm west of the Divide. April 5-8th saw generally stable weather, with some convective flurries. Daytime temperatures hovered around 0 degrees at treeline with strong solar radiation, making it feel much warmer. A clear, cold night on April 7th while camped near Peyto Hut saw temperatures drop to -17 overnight, with moderate west winds picking up the following morning. Our ski out from the Wapta on April 8th saw continuing variable mod-strong winds ranging from north towest, transporting snow and creating new windslabs.
 
The main snowpack concerns throughout the week were as follows. The 40-50cm of snow from earlier in the week hasbeen redistributed by moderate to strong winds forming newwindslabs in the alpine. A series of buried windslabs are present on all aspects. Buried suncrusts and new surface crustswere found on solar aspects. One of the main layers of concern is the March 28th crust/facet layer now buried 30-60cm. Tests on this layer show that it’s still within the realm of human triggering. Below this, is a well settled midpack, with the facets/depth hoar still lingering in all areas at the bottom of thesnowpack. A smaller avalanche ‘stepping down’ to these basal facets, a large trigger (cornice) or triggering it from a thin snowpack area was a big concern, with potential for large destructive avalanches. There is an above average snowpack depth in the Rockies for this time of year, providing good coverage on the glaciers. Snow depths ranged from 50cm in shallow areas to 300cm+ on the glaciers.  
Later in the week, daytime warming produced multiple loose snow avalanches on solar aspects. Cornices are looking very large, and we saw a few cornice triggered slab avalanches from earlier in the week. We saw some serac activity, specifically off the north face of Mt.Gordon.
We skied conservatively, limiting our exposure to overhead hazard and steep slopes, but found good powder skiing with the best being on the more sheltered, northerly aspects.  Unfortunately, yesterdays winds will make it a bit harder to find non-wind affected snow in the alpine.

Reported by ACMG Assistant Ski Guide exam candidates and assessors.





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