This bulletin is based on limited data. Local variation in conditions and danger levels are likely to exist. To produce more accurate forecasts, we need information. Please send an email to forecaster@avalanche.ca.
Summary
Confidence
Poor - Due to limited field observations
Weather Forecast
Saturday: Mostly cloudy, but no precipitation. Temperatures reaching -5 and winds will remain light. Sunday: More clouds with flurries developing later in the day and highs of -5. Winds light Southwesterly but increasing through the day. Monday: Snow, at times heavy. Winds continue Southwesterly and temperatures climbing to -2.
Avalanche Summary
Recent reports include wind slab avalanches up to Size 2.5 failing on a surface hoar layer that was buried earlier this week. Some slabs were up to a metre deep and pulled back into low angled terrain on ridges showing incredible propensity for propagation. Wind and storm slabs will likely remain susceptible to human triggering throughout the weekend, and probably much longer in areas where they're failing on surface hoar a facet/crust combination.
Snowpack Summary
Another 20-30cm of upside-down storm snow brings total snowpack depths up to a metre or so in sheltered treeline areas, but expect to find much deeper pockets of wind-blown snow immediately down-wind of terrain features and ridge crests. A thick rain crust from last week is 70 or 80 cm off the ground at treeline and lower alpine elevations, with facets above and below in some locations. Above that is a buried layer of surface hoar that formed during the clear weather over the weekend. These weaknesses now have a sufficiently thick and cohesive slab to produce avalanches in most areas and they have all the characteristics of an avalanche problem that could persist for extended periods.
mpeter,
Avalanche Canada
