Regions
Kootenay Boundary.
Resist the urge to rely on danger ratings alone. Conditions change rapidly at this time of year and you need to stay tuned in to local conditions.
Confidence
Poor - Due to the number of field observations
Weather Forecast
Monday: A mix of sun and cloud becoming overcast in the afternoon with light flurries / Moderate southerly winds / Freezing level at about 2000mTuesday: 10-20cm of wet snowfall at higher elevations / Moderate southerly winds / Freezing levels are uncertain, although some models are indicating up to 2500mWednesday: Mainly overcast skies with light flurries / Moderate southerly winds / Freezing level at about 1800m
Avalanche Summary
In Kootenay Pass on Saturday there was a loose wet avalanche cycle to size 1.5 on steep, sun-exposed terrain. We also received a report of a skier triggered size 1.5 loose wet avalanche close to Nelson.
Snowpack Summary
Note: We have very little recent data to base this summary on. If you're out in the mountains ask other locals about the current conditions and spend some time making snow and weather observations to help assess local hazard. Up to 15cm of new snow is estimated to have fallen at upper elevations on Saturday night. Below about 1600 m rain continued to saturate the snowpack. Generally moderate westerly winds have shifted the new accumulations into wind slabs in lee upper elevation terrain. Although the new snow is expected to stabilize quickly with Sunday's warm temperatures, I'd be cautious in the immediate lee of high elevation terrain breaks and ridge crests. Warm temperatures and solar radiation have created moist surfaces in many other areas. If there is a good overnight freeze these surfaces will exist as a harder crust.The late January/early February persistent weak layer is deeply buried but could still wake up during periods of heavy precipitation (especially rain) or significant warming and solar radiation. Cornices are large in some areas and should be given a wide berth.
Problems
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.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.