Avalanche Forecast
Regions: Northwest Coastal.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
SUNDAY NIGHT: Clearing / Light, northeasterly winds / Alpine low -2 C / Freezing level 1500 m.MONDAY: Sunny / Light, northeasterly winds / Alpine high 2 C / Freezing level 1500 m.TUESDAY: Sunny with cloudy periods / Light, southwesterly winds / Alpine high 2 C / Freezing level 1500 m.WEDNESDAY: Mix of sun and cloud / Moderate, southeasterly winds / Alpine high 2 C / Freezing level 1600 m.
Avalanche Summary
Natural avalanche activity has tapered off but concern remains for human triggering persistent slab avalanches on a layer of facets that are down 50-100 cm. Explosive control work on Thursday produced several large avalanches, up to size 3, on this layer.
Snowpack Summary
At upper elevations, 50-100 cm of well settled snow overlies weak facets (sugary snow) that were buried around March. 10th. which is currently the primary layer of concern for human triggering persistent slab avalanches.Not much further below the March 10th interface is a second weak layer of facets buried on February 19th. Recent loose wet and slab avalanches have been observed gouging into this faceted snow and entraining additional mass.The prolonged warm spell has transitioned sun exposed slopes in the alpine and all aspects at treeline and below towards becoming isothermal (0 C throughout the snowpack). In these areas that have entered spring conditions, the avalanche hazard will fluctuate greatly depending on the strength of the overnight freeze and how quickly the snowpack is warmed up each day. Check out this guide to managing avalanche hazard during spring conditions HERE.
Avalanche Problems
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1.5 - 2.5
Loose Wet
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood: Possible
Expected Size: 1 - 2