Avalanche Forecast

Issued: Mar 20th, 2019 3:40PM

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

swerner, Avalanche Canada

Sea To Sky.

Natural avalanche activity is possible especially on sun exposed slopes in the afternoon. Cornices are soft and weak. Avoid travel under, on or anywhere near cornices.

Summary

Confidence

Moderate -

Weather Forecast

Change in the weather pattern is on the way. Starting with cloudy skies, falling temperatures and freezing levels by the weekend. THURSDAY: Mostly cloudy. Freezing levels 2300 m and alpine temperatures near +5 degrees. Ridgetop winds light from the southeast.FRIDAY: Cloudy. Freezing levels falling to 1600 m and alpine temperatures near +1. Possible weak temperature inversion. Ridgetop winds light from the southeast.SATURDAY: Cloudy with light precipitation (5-10 mm) falling as rain at treeline and below treeline and snow in the alpine. Freezing levels 1500 m and alpine temperatures falling to -2. Ridgetop winds light from the South.

Avalanche Summary

On Tuesday, several natural and skier triggered loose wet avalanches up to size 2 were reported on all aspects and elevations from the region. Active cornice control with the use of explosives successfully dropped some chunks up to size 2 without pulling slabs on the slopes below. Natural avalanche activity may start to taper off with cooler temperatures this weekend.

Snowpack Summary

Snow surfaces are highly variable. On higher elevation north aspects (above 1700 m) you may find some dry, faceted snow. Some of this has been redistributed by southwesterly and northerly winds, potentially creating some unusual wind slabs. On solar aspects (East, South, West) moist snow surfaces exist creating melt-freeze conditions at higher elevations and mostly just melt conditions below treeline.The bigger questions are deeper in the snowpack. With little overnight re-freeze the warm temperatures will penetrate deeper and continue to destabilize the snowpack. Its hard to say how many hot days and warm nights it will it take to wake up the more deeply buried weak layers that we haven't thought about in a long time.

Problems

Loose Wet

Loose wet activity is expected to continue on all aspects and elevations except northerly alpine slopes. Cornices are soft and weak. You don't want to be under or near one of these monsters when they fail.

Loose avalanches may start small but they can grow and push you into dangerous terrain.Cornices become weak with daytime heating or solar exposure.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Wind Slabs

Continued warm temperatures will further destabilize the upper 30 to 50 cm of snow which has potential to fail naturally.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Back off slopes as the surface becomes moist or wet with rising temperatures.

Aspects: North, North East, North West.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 21st, 2019 2:00PM