Regions
Vancouver Island.
Reports from steep skiing on North aspects at 1400 meters indicate that the new snow that has fallen is very loose and dry. This snow is easy to trigger on steep terrain, producing Loose dry avalanches up-to size 1. One soft storm slab was trigger on a steep convex roll and was size one.
A skier trigger a size one storm slab avalanche on a steep convex roll near Mount Beecher. Previous to triggering this avalanche the party reported seeing other signs of instability , cracking and settling.
There was no involvement, injuries or lost gear in any of these reports.
Past Weather
A flurry of convective storm activity brought to the forecast region a variety of weather conditions all with snowfall. Western regions experienced amounts in excess of 40 cm and Eastern 10 to 20 cm. Temperatures remained relatively low with freezing levels remaining below 1000 meters.
Weather Forecast
Periods of unstable weather will deliver a variety of conditions, expect Tuesday a low pressure to bring increased wind and moderate snowfall.Monday 5 cm of new snow. Winds Light Southwest. Freezing levels 1000 meters.Tuesday 15 to 30 cm of new snow. Winds Strong Southwest. Freezing level 1200 meters.Wednesday 5 cm of new snow. Winds light to moderate Northwest. Temps -5 to -8. Freezing level 1000 meters.
Terrain Advice
Careful and cautious route finding when transitioning into wind effected convex rolls or steep terrain.Default to lower angled terrain if you observe wind drifted snow, active snow transport, or snowfall amounts that exceed 30 centimeters.
Snowpack Summary
A refresh of new storm snow overlies previous old snow surfaces. In protected areas this snow is low density and well preserved. In areas that are exposed to the wind and sun , the snow is settling and are becoming consolidated and slab like.
Snowpack Details
- Surface: New snow of up to 40 overlies over a thin sun crust on solar aspects and on old hard snow on non solar.
- Upper: 30 to 100 cm of settled storm snow with a few thin crusts sandwiched between on solar aspects.
- Mid: An old crust with weakening snow crystals above and below the crust as it continues to degrade.
- Lower: Well settled and dense.
Confidence
Moderate - A high degree of variability between forecast snowfall amounts in western and eastern zones of the forecast area.
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.
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.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.