Avalanche Forecast
Regions: Northwest Coastal.
Weather Forecast
A mix of sun and cloud is expected for Wednesday but light flurries may continue in the morning. Light southerly winds are expected in the alpine and afternoon freezing levels should be around 1400m. Mostly sunny conditions are expected Thursday morning with increasing cloudiness in the afternoon. Winds should remain light most of the day and afternoon freezing levels are expected to be around 1600m. Light snowfall is expected on Friday. Alpine winds are forecast to be moderate to strong from the southwest with afternoon freezing levels around 1300m.
Avalanche Summary
On both Sunday and Monday, loose wet avalanches up to size 2.5 were reported in the far north of the region. With the arrival of spring, field observations and data have become quite limited in the region. A lack of avalanche reports does not mean avalanches are not occurring. On Wednesday, newly formed wind slabs are expected to be reactive to human-triggering in the alpine. Widespread solar triggered loose sluffing is expected with the new snow sliding on the firm crust layer. Cornices have been weak recently and may fail naturally with storm loading.
Snowpack Summary
Prior to the new snowfall, dry winter snow was being reported on northern aspects above 1700m in the area north of Stewart. South aspect slopes and lower elevations were undergoing daily melt-freeze cycles. Around Terrace, melt-freeze conditions were reported at all elevations. The new snow will bury this crust and strong southerly winds in the alpine will build wind slabs. The region should return to melt-freeze conditions on Wednesday with surface crusts forming overnight and breaking down during the day. The snowpack's strength is directly related to the thickness and strength of these surface crusts. A widespread crust/facet layer from early February and depth hoar at the bottom of the snowpack (primarily in northerly & inland areas) are dormant. Cycles of melting and refreezing have limited the reactivity of these old layers. However these layers, or the ground, could potentially once again be the layer for an isolated yet large avalanche with prolonged periods of warming.
Avalanche Problems
Loose Wet
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 3
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood: Possible - Likely
Expected Size: 1 - 3
Cornices
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 2 - 5