Conservative terrain selection is critical for safe riding in the backcountry these days. Pay attention to rising temperatures and be wary of cornices.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
A high pressure ridge is re-establishing itself over most of BC bringing mostly sunny skies with a few cloudy periods. No precipitation is forecast for the next 4 or 5 days. Freezing levels may rise as high as 1500 metres during the day, then drop to valley bottom overnight. On Thursday the freezing level is forecast to rise to 3000 metres with clear skies.
Avalanche Summary
Natural avalanche activity appears to have slowed down west of the divide. On the eastern slopes there were reports of 3 size 1.5 - 2 natural avalanches that occurred in the past 24 hrs. on NE aspects at 1900m. Most likely as a result of the wind loading that occurred during the last precipitation and wind event.
Snowpack Summary
New snow with wind during the weekend contributed to wind slabs forming in lee terrain at treeline and in the alpine. A melt freeze crust which formed during the 2nd week of February has been reported between 40 and 70 cm., perhaps more deeply buried in the south of the region. This crust layer has also been reported with surface hoar in some places, for the most part on high and north facing terrain. Rain and warm temperatures at lower elevations created a 2 to 4cm rain crust, on south aspects below 1800 m. West of the divide, a layer of buried surface hoar might be found between 70 and 90cm below the surface. Recent reports suggest this layer has become less of a concern. As well, the stormy weather has encouraged new cornice growth. These cornices are reported to be huge and unsupported. With warm weather and sun in the afternoon, these could become a significant hazard.
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.
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.