Storm slabs have formed with recent snowfall. Expect them on all aspects with thicker slabs in lee features, loose dry snow in sheltered areas, and looming cornices on ridgelines. Treat the hazard higher if you see more snow than forecasted.
Confidence
Moderate - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
SATURDAY NIGHT: Cloudy with snowfall, accumulation 10 to 25 cm, strong westerly winds, alpine temperature -10 C, freezing level 500 m.SUNDAY: Cloudy with intermittent snowfall, accumulation 5 cm, light to moderate westerly winds, alpine temperature -13 C, freezing level near 500 m.MONDAY: Partly cloudy, light westerly winds, alpine temperature -12 C, freezing level 700 m.TUESDAY: Cloudy with light snowfall, accumulation 5 cm, light to moderate westerly winds, alpine temperature -10 C, freezing level 800 m.
Avalanche Summary
Small loose and slab avalanches were observed at treeline and alpine elevations on Saturday, triggered by skiers, explosives, and naturally.Expect natural and human-triggered avalanche activity to increase with the recent snowfall and strong winds.
Snowpack Summary
Around 10 to 20 cm of storm snow fell on Friday and another 25 cm of snow could fall in parts of the region Saturday night, and light flurries are expected Sunday morning. These storms have had strong south to westerly winds associated with them. Expect touchy storm slabs on all aspects with thicker slabs found in lee features. All of this snow fell on previously wind-affected surfaces as well as a sun crust on solar aspects. The new snow may not bond well to these surfaces and could be reactive to both natural and human triggers.Also make note of cornices at ridgeline. Variable winds in the past month have produced cornices on all aspects. They will become touchier as they grow in size, as temperatures rise, and as the sun packs a strong punch on clear days. Stand well back of them and avoid them from below!
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.