Regions
Northwest Inland.
New storm snow and forecast strong winds are increasing the avalanche danger.
Confidence
Fair - Intensity of incoming weather systems is uncertain
Weather Forecast
Overnight and Friday: Light to moderate snow this evening, ending by morning. Strong Westerly winds and freezing levels down to valley bottoms. Some flurries during the afternoon Friday.Saturday:Pacific moisture is expected to push inland bringing 10-15 cms during the day. Winds building to very strong Southwest. Freezing level rising to 1500 metres.Sunday:Snow ending by early morning. The winds should slow a bit, but remain strong Southwesterly. Freezing level dropping throughout the day.
Avalanche Summary
New storm snow is expected to increase the avalanche danger. The weak shallow snowpack may not support the added load of new storm snow. Strong winds, new snow, and rising temperatures are expected to increase the sensitivity to triggering by skiers and sledders.
Snowpack Summary
Snowpack depths are likely highly variable across the region, with elevation, and in wind-exposed areas. Recent cold and clear weather has resulted in surface hoar formation and/or near surface facetting, which is now getting buried by light dry snow. Low-elevation and wind-affected areas likely have a shallow faceted snowpack. While in higher elevation sheltered areas the recent storm snow is likely settling and gaining strength; however, weaknesses at the old snow interface down approximately 40cm may still exist. Average snowpack depths near treeline are highly variable, but around a metre in sheltered areas.
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.