Weather Forecast
A firmly embedded ridge of high pressure over Alberta seems to be causing systems to fizzle once they reach the Columbia Mountains. Conditions will be mostly cloudy for the forecast period with the possibility of trace amounts of snowfall each day. Winds will be light and northwesterly with alpine temperatures trending from -7.0 on Saturday to -13.0 by Monday.
Avalanche Summary
No new avalanche activity to report.
Snowpack Summary
In general, the upper snowpack is now well settled and riders are shredding pretty much everything. Very warm alpine temperatures from last weekend melted snow surfaces and a crust now exists to ridge top on solar aspects. There are reports of wind slabs in the alpine that developed earlier in the week. My feeling is that they are not widespread and probably gaining strength. Deeper weaknesses in the snowpack are less of a concern; however, in the southern end of the region there is still talk of basal facets as some operators are avoiding thin and rocky alpine features. This represents a very low probability-high consequence scenario. Large cornices are also widespread in the alpine. A dusting of new snow now sits on weak snow crystals that developed over the past week (surface hoar/crusts/facets). This will be the big thing to watch as the overlying slab evolves.
Problems
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.