Avalanche Forecast

Issued: Apr 12th, 2016 8:00AM

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

ian gale, Parks Canada

Glacier.

Spring skiing is here. Early starts and early finishes are crucial to playing safe! Although supportive in the morning, the upper snowpack is moist and will breakdown quickly with daytime warming.

Summary

Weather Forecast

There'll be a shift in the weather pattern today with the upper ridge being pushed out by a cool upper trough. Today will be a mix of sun and cloud with little to no precip, ridgetop wind will be SW 20kph gusting to 60. Freezing level will rise to 2200m late morning and start to drop in the afternoon. Up to 8cm of snow is forecasted for tonight.

Snowpack Summary

We experienced a good freeze in the valley bottom overnight but a temp inversion kept the alpine temps above zero overnight. The clear windy night will have created a marginal surface crust but this will break down with daytime heating & sun. Recent winds have likely redistributed remaining dry snow in the alpine leaving variable wind slabs

Avalanche Summary

We have been experiencing regular natural avalanche cycles in the afternoon with daytime warming and the strong effects of the sun. Avalanches have been in the sz 1.5 - 2.5 range and either loose wet or wet slab releases. Sporadic glide crack releases to sz 3 have been witnessed every few days which are large, destructive & tricky to forecast

Confidence

Problems

Loose Wet

It doesn't take long for the strong solar & warm temps to break down the weak surface crust. Loose wet avalanches are expected. Be especially careful on S aspects & in terrain traps below treeline where even small slides could bury or push you around

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.Avoid exposure to solar aspects overhead, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Wet Slabs

Strong solar input and daytime warming have created a wet slab problem. These slabs can be triggered from loose point releases or they can fail seemingly unprompted in the form of a large glide release. Avoid overhead exposure to glide cracks!

Avoid lingering in runout zones.Use caution on open slopes and convex rolls

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Cornices

Cornices along ridges will be weakened by the sun & warm temps. Serac fall from glaciers has also been observed recently. Pieces of cornice or ice crashing down are concerns in their own right but these can trigger larger avalanches once on the slope

Give cornices a wide berth when travelling on or below ridges.Cornices become weak with daytime heating, so travel early on exposed slopes.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 13th, 2016 8:00AM