Regions
Northwest Inland.
Forecast new snow and wind are expected to develop new wind slabs in the alpine. Persistent weak layers continue to be a concern for large human triggered avalanches.
Confidence
Moderate - Freezing levels are uncertain
Weather Forecast
A series of Pacific disturbances are lining up to hit the coast over the next few days. Light precipitation is expected to push inland on Friday, Saturday, and Sunday. Light snow (3-5 cm) should fall in the alpine and at treeline as the freezing levels fluctuate between 600-1200 metres over the next few days. A warm and wet storm is forecast for Monday.
Avalanche Summary
No new avalanche observations. A widespread natural avalanche cycle to size 3 took place on Monday in response to recent storm loading and then rain. Avalanche types observed were loose wet, wet slabs, storm slabs and persistent slabs. Cooling will help reduce avalanche activity; however, the forecast cooling trend is so gradual it's tough to say exactly when or to what extent.
Snowpack Summary
Recent storm snow is settling due to warm temperatures and high freezing levels. Some isolated wind slabs may develop in the alpine where dry storm snow is available for transport. Loose wet snow may be easily triggered at lower elevations that have not experienced a re-freeze since the last storm. Crusts may be developing at mid-elevations as the freezing level slowly descends. Within the top 50cm you may find a layer of surface hoar which was buried at the beginning of February. This layer was observed in the Hankin area and may exist in many other places. The early or mid January surface hoar layer is generally 50-80 cm deep, although it may be buried by well over 100cm of snow in the far west of the region. Observers have found this persistent weakness on all aspects and at all elevations. It consistently produces moderate "pops" results in snowpack tests. Below this, the Boxing Day surface hoar problem may also be lurking. The mid and lower snowpack is generally quite weak and faceted, especially in lower snowpack areas such as the Babines.
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.
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.
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.