Wind slabs remain the main avalanche concern. If temperatures rise we may start to see solar triggered avalanches and cornice failures over the next few days. Ice climbers should pay extra attention to the warming effect on snow and ice conditions.
Weather Forecast
A mix of sun and cloud, mild temperatures and light to moderate winds shifting from the W to the N over the next few days is expected as a strong ridge of high pressure builds into B.C. Freezing levels will rise to near 1500m during the day and expect a strong solar effect if the skies are clear. Some flurries may be possible on Saturday evening.
Snowpack Summary
5-10 cm of new snow with light winds in the last 48hrs. Moist surface snow on steep South aspects today. The new snow sits over the previous sun crust and wind slabs and appears to be bonding well in most locations. Some new wind slabs have formed near ridge crests and in the alpine. Below is a well settled snowpack with no significant weaknesses.
Avalanche Summary
A couple of avalanches up to size 2 have been observed out of extreme terrain in the last 48hrs. One appears to have been cornice triggered and likely occurred due to daytime warming today. If the clear weather and mild temperatures continue we will likely see more avalanche activity or cornice failures due to solar heating in the next few days.
Confidence
Timing or intensity of solar radiation is uncertain
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.