Archived

Avalanche Forecast

Apr 9th, 2016–Apr 10th, 2016

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

Below Threshold

The avalanche danger rating in the alpine will be below threshold

Treeline

Below Threshold

The avalanche danger rating at treeline will be below threshold

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Regions: Glacier.

Travel is safer early in the day. Expect crusts to break down quickly with daytime warming and solar input, leading to dangerous avalanche conditions on all aspects.

Weather Forecast

Full sun today with freezing levels rising to 2100m. Ridge winds vary from light to moderate from the NW. Clear skies and cooler temps may promote a refreeze of the snowpack tonight with freezing levels dropping to 1400m. Warm daytime temperatures will persist into next week. The high pressure ridge will break down on Tuesday bringing light rain.

Snowpack Summary

Daytime warming turned the recent storm snow into a 30cm moist layer. There was no full refreeze last night, but under clear skies a weak surface crust likely formed. Below the crust the upper ~70cm of snow is warm, moist and weak. Extreme southerly winds have likely spoiled any remaining north facing powder stashes leaving touchy wind slabs.

Avalanche Summary

Several loose wet avalanches were observed in the highway corridor up to size 2.5. Some time yesterday evening, a large mid-elevation glide crack released on Mt MacDonald creating a large size 3 avalanche.

Confidence

Avalanche Problems

Loose Wet

We have yet to undergo a true melt-freeze cycle due to warm overnight temps and the snowpack is generally weak. It doesn't take long for the strong solar and very warm temps to break down the weak surface crust. Loose wet avalanches are expected.

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

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 2 - 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.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 4

Cornices

Huge cornices along ridges will be weakened by the strong sun today and continued above freezing temps. A chunk of cornice tumbling down-slope is a concern in itself, but cornices failures also provide a heavy trigger and may trigger large avalanches

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

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 3