Regions
Northwest Coastal.
Weather Forecast
Wednesday: 10-15cm of snow is expected with freezing levels remaining in valley bottoms and moderate southeasterly winds. Thursday: Another 10cm or so of new snow, with freezing levels remaining in valley bottoms and light to moderate southerly winds. Friday: 20-30cm of new snow with freezing levels remaining in valley bottoms and moderate southerly winds.
Avalanche Summary
Reports from Monday include several small human-triggered loose snow and soft wind slab avalanches involving the recent storm snow.
Snowpack Summary
15-25cm of unconsolidated new snow is bonding poorly a variety of old surfaces which include: a crust at lower elevations and on solar aspects; old wind slabs in exposed areas, and fairly widespread large surface hoar. Moderate to locally extreme west/southwest winds have redistributed the new snow into soft and hard wind slabs in exposed terrain. This new snow is currently reactive to human triggers primarily where cohesive wind slabs have formed, but reactivity is expected to become more widespread as the overlying slab develops with continued loading. The mid snowpack layers are generally well settled and strong. Facets at the base of the snowpack may resurface as a concern now that spring warming is on the doorstep and full-depth releases are becoming more likely (primarily in the northern part of the region).
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.