Avalanche Forecast

Issued: Dec 7th, 2017 3:54PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Loose Wet and Wind Slabs.

mconlan, Avalanche Canada

Sea To Sky.

Spring-like conditions should continue. Be cautious on steep slopes if the snow feels moist or wet.

Summary

Confidence

High - The weather pattern is stable

Weather Forecast

FRIDAY: Sunny, light to moderate southwesterly winds, freezing level around 3000 m.SATURDAY: Increasing cloud with trace precipitation, moderate to strong southwesterly winds, freezing level around 2500 m.SUNDAY: Mostly sunny, light to moderate southwesterly winds, freezing level around 3400 m.

Avalanche Summary

Numerous loose wet avalanches up to size 2 were observed within the region on Wednesday. Widespread pin-wheeling and snowballing was observed from steep, sun-exposed terrain. One wet slab was triggered from a loose wet avalanche around treeline, which was suspected to have released on a late-November rain crust.

Snowpack Summary

Dramatic warming and clear skies have caused widespread melting of the surface snow, especially on south-facing slopes. Crusts may form overnight but they will melt quickly in the mornings. Surface hoar is growing at and near treeline in shady locations and during the nights, but it may melt with the warm temperatures. The 40-60 cm of storm snow that fell last week is rapidly settling and generally bonding well to the late-November rain crusts. At high elevations, shifting winds (first from the south, and more recently from the north) have blown snow around in exposed areas creating drifts and scoured areas.

Problems

Loose Wet

Warm air temperatures and clear skies are producing spring-like conditions. Loose wet avalanches may begin small but can grow and push you into dangerous terrain.

Avoid sunny slopes when the solar radiation is strong, especially if the snow is moist or wet.Use caution above cliffs and terrain traps, where small avalanches may have severe consequences.Loose wet avalanches may trigger deeper layers resulting in larger avalanches.

Aspects: North, North East, East, South East.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Wind Slabs

Isolated winds slabs have formed on a variety of aspects at higher elevations and in some cases sit above a buried crust. Caution is advised on steep terrain adjacent to ridges.

Be alert to changing snow conditions, especially where the snow firms up or sounds hollow.Avoid steep lee and cross-loaded features

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Dec 8th, 2017 2:00PM