Avalanche Forecast
Regions: Sea To Sky.
Avalanche conditions will become more dangerous throughout the day. Avoid avalanche terrain in areas that receive more than 20 cm of new snow.
Confidence
High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.
Weather Forecast
A frontal system will bring heavy snowfall Saturday night and Sunday.
SATURDAY NIGHT: 10-15 cm of new snow, strong south wind, freezing level around 1000 m and treeline temperatures around -4 C.
SUNDAY: Flurries continue with another 15-25 cm of snow bringing 2-day storm totals to 25-40 cm, moderate to strong south wind, freezing level around 1200 m and treeline temperatures around C.
MONDAY: Mainly cloudy with isolated flurries and a trace of new snow, light wind, freezing level around 1100 m and treeline temperatures around -4 C.
TUESDAY: Scattered flurries with 10-20 cm of snow, moderate southwest wind, freezing level around 900 m and treeline temperatures around -6 C.
Avalanche Summary
Recent avalanche activity has been limited, following a pattern of human and explosives triggered small (size 1) releases; wind slabs where wind loading has occurred and loose dry where it hasn't.
Looking forward, expect progressively touchy conditions and increasing hazard with forecast new snow and wind. Along with the usual surface instabilities, concern for a recently buried weak layer is also rising in step with this active weather.
Snowpack Summary
25-40 cm of new snow, favouring the south of the region, is expected to accumulate by the end of the day on Saturday. This will add to 10-20 cm of recent snow sitting on firm, wind affected snow at upper elevations, on surface hoar in sheltered areas, on a melt-freeze crust below 1900 m, and on a sun crust on south-facing slopes.
A crust from early December may be found around 200 cm deep in the snowpack. In shallow rocky areas, recent test results suggest that it may still be possible to trigger this layer. In deeper snowpack areas it has shown no recent results and appears to be unreactive in these areas.
Terrain and Travel
- Storm slab size and sensitivity to triggering will likely increase through the day.
- Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.
Avalanche Problems
Storm Slabs
By Sunday afternoon there will likely be 25-40 cm of fresh snow, resulting in thick and touchy storm slabs. Expect natural avalanches in steep and wind-affected terrain during periods of heavy loading, while human triggered avalanches will be likely throughout the day. Storm slabs may propagate widely as they sit atop a recently buried weak layer.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 2.5