Warm air and sunny skies will influence the snowpack on Saturday. The amount of warming is uncertain; expect the most warming on south aspects and for the snowpack to possibly moisten on other aspects too. This may make the snow very touchy.
Confidence
Moderate - Freezing levels are uncertain
Weather Forecast
FRIDAY NIGHT: Clear skies, freezing level rising to 3000 m.SATURDAY: Clear skies, light northwest winds, alpine temperature between 3 C and 6 C, freezing level 3200 m with inversion conditions.SUNDAY: Clear skies, moderate northwest winds, alpine temperature between -1 C and 2 C, freezing level dropping from 2500 m to 2000 m over the day.MONDAY: Clear skies, light north winds, alpine temperature -3 C, freezing level 1000 m.
Avalanche Summary
Wet loose avalanches were observed on southerly aspects on Thursday. The likelihood of these avalanches should increase with warm air temperatures invading the province.
Snowpack Summary
The snow surface may moisten with warm air temperatures on all aspects, but most pronounced on southerly aspects. Beneath this, around 40 to 60 cm of snow sits on a sun crust on south aspects and weak and feathery surface hoar in sheltered and shaded areas. The surface hoar is likely most pronounced at treeline and upper below treeline elevations.The remainder of the snowpack is generally well-settled.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.