Winter temperatures, winter snow, and winter avalanche problems! It's all back... bring your smile, your skis / snowshoes, your avalanche rescue equipment, and your savvy.
Weather Forecast
A little more snowfall for Sunday night, with cooling temperatures - models disagree as to just how much, but upto 10cm. Monday-Wednesday, expect winter-like temperatures, and unsettled weather: a mix of sun & cloud, with the odd flurry. Strong Westerly winds on Monday gradually ease to Light Westerlies by Wednesday.
Snowpack Summary
25-40cm of snow has fallen since Thursday, accompanied by strong SW winds and warm temperatures . This has created dense Storm Slabs on lee slopes, bonding poorly to a crust below. A deeper crust down 60-100cm has produced alarming results in some snowpack tests at Treeline, although slope tests did not produce avalanches on this layer.
Avalanche Summary
On Saturday and Sunday, several small Storm Slab avalanches were observed in lee terrain. These started in steep terrain, or under headwalls. Two very large avalanches were observed recently near the divide. These began in steep, unsupported terrain. The dates of these are unknown, but warm storms on March 6 or March 10 were likely responsible.
Confidence
Forecast snowfall amounts are uncertain on Sunday
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
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.