Avalanche Forecast

Issued: Apr 5th, 2017 4:29PM

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

Avalanche Canada mbender, Avalanche Canada

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Summary

Confidence

Low - Due to the number of field observations

Weather Forecast

THURSDAY: Flurries or rain showers, accumulation 5-10cm / Moderate south wind / Alpine temperature 1 / Freezing level 2000mFRIDAY: Flurries, accumulation 10cm / Moderate to strong south wind / Alpine temperature 1 / Freezing level 2000mSATURDAY: Flurries, accumulation 5cm / Moderate southwest wind / Alpine temperature -4 / Freezing level 1300m

Avalanche Summary

On Thursday, the main concern is lingering wind slabs in high elevation north facing terrain and the possibility of large overhanging cornices releasing with overall warm temperatures over the coming days.

Snowpack Summary

The region is expected to have entered a period of widespread melt-freeze conditions on all aspects and elevations except for high north facing terrain where the surface snow is expected to remain dry. In high elevation terrain, recent strong southwest winds and new snowfall has formed wind slabs in leeward features. At lower elevations and on sun exposed slopes, there are likely several well bonded crust layers in the upper snowpack. A rain crust which was buried on March 21 extends into the alpine is now down 60-80 cm. This crust was the bed surface for several avalanches during the solar cycle at the end of last week. At elevations above around 2100m, the February persistent weak layers may still be lingering down around 100-150cm and weak basal facets may still be lingering in shallow snowpack areas. These deep weak layers appear to have gone dormant but an isolated avalanche or cornice fall still has the potential to step down in the right conditions.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs have recently formed in north facing terrain at higher elevations and are expected to remain reactive to human triggering.
Use caution on steep open slopes and unsupported convex rollsUse ridges or ribs to avoid pockets of wind loaded snow.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Cornices

An icon showing Cornices
Large cornices are expected to become weak with daytime warming and/or sustained sun exposure.
Give cornices a wide berth when travelling on or below ridges.Pay attention to overhead hazards like cornices which could trigger a deeper buried weak layer.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 6th, 2017 2:00PM