Regions
Vancouver Island.
No new avalanches reported in the past 48hrs.
Past Weather
Cool air temperatures and moderate storm snow events have deposited 1 foot (30 cm) or more of snow onto the snowpack over the course of this past weekend.
Weather Forecast
Tuesday 7 - 12mm Rain and 7 - 21 cm Snow , Winds Strong to Moderate from the South, Freezing level shifting from 300M to 2500M later in the day. Wednesday 6- 40 mm Rain, Winds Strong transitioning to Light later in day from the West, Freezing level shifting from 2500M to 1400 meters.Thursday 3-12 cm, Winds Light transitioning from the North to the South, Freezing level 1500 meters.
Terrain Advice
Natural Avalanches possible. Human triggered avalanches likely in the Alpine. There is a good amount of precipitation expected over the next 48 hours on Vancouver Island. Be aware as you move through the terrain for shooting cracks and signs of instability (including new avalanches) especially at Treeline and Alpine elevation bands. Convex unsupported terrain features in leeward (down wind) terrain would be an area to be highly cautious of when navigating through the backcountry this week. Allow for an additional 36-48 HRS before stepping onto leeward terrain (downwind) areas particularly if the forecasted precipitation of 30+cm of new snow or Rain AND/OR signs of snow transport by strong winds exists in your area.
Snowpack Summary
A variety of melt freeze crusts exist within the upper snowpack. The more recent snowfall from Sunday's cooler temperatures have deposited fresh snow on the most recent melt freeze crust. Snowpack tests are providing results on this layer, as more winds travel through the area today and tommorow we should expect substantial new wind loading and likely wind slab avalanche hazard in leeward (downwind) terrain. The massive rain events from the past week added major moisture content to the Vancouver Island snowpack. Fortunately, with the more recent cooler (below zero) air temperatures we have experienced, the snowpack has consolidated. The most important hazard at this time exists within the upper 10 to 40 cm of the snowpack and exists as a result of new storm snow and wind activity that has occurred in the past 48 Hours.
Snowpack Details
- Surface: 10 -40 cm of light dry storm snow and/or firm wind loaded snow in leeward terrain
- Upper: Melt freeze crust that is providing results on testing as new snow gradually bonds to this crust layer
- Mid: Well Bridged due to abundance of moisture in snowpack and below freezing air temperatures
- Lower: Well Settled
Confidence
High - Sufficient field weather and snowpack observations
Problems
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
Wet Slabs
Wet Slab avalanches are the release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slabs can be very unpredictable and destructive.
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.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.
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.