Regions
Northwest Coastal.
Wet and snowy weather is approaching. Avalanche danger will increase as new snow accumulates and is redistributed by wind.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
WEDNESDAY NIGHT - Cloudy with clear periods / southwest wind, 25-35 km/h / alpine low temperature -5 C / freezing level 500 m THURSDAY - Flurries, 10-15 cm accumulation by end of day / south wind, 25 gusting to 40 km/h / alpine high temperature 0 C / freezing level 1000 mFRIDAY - Wet flurries, 7-12 cm accumulation / south-southeast wind, 20-45 km/h / alpine high temperature +2 C / freezing level 1500 mSATURDAY - Snow, 10-30 cm accumulation / south-southeast wind, 20 gusting up to 100 km/h / alpine high temperature 0 C / freezing level 1300 m
Avalanche Summary
Last Friday, there were reports of a few size 2 loose wet and wet slab avalanches on southerly aspects. The likelihood of loose wet avalanches on sun-affected slopes will increase throughout the day as the sun comes out and temperatures rise.
Snowpack Summary
Sun exposed slopes in the alpine and on all aspects at treeline and below have become moist to wet during the heat of the day. In these areas spring conditions are in effect; the avalanche hazard will fluctuate greatly depending on the strength of the overnight freeze and how quickly the snowpack is warmed up each day. Dry snow may remain on north-facing slopes in the alpine. In these locations, 50-100 cm of snow sits on a layer of facets (sugary snow) that was buried around March 10th.
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.