Avalanche Forecast

Issued: Mar 18th, 2016 8:00AM

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

andrew jones, Parks Canada

Glacier.

Watch for changes in stability as the spring sun warms the snowpack. Persistent avalanche problems remain touchy on unsupported and exposed features above treeline.

Summary

Weather Forecast

An upper ridge of high pressure dominates the weather today bringing the spring sun and freezing levels below 1500m. No precipitation is expected and ridge winds will remain light. Freezing levels begin to rise this weekend as the ridge breaks down and another low pressure system moves in. Freezing levels peak at 2500m on Sunday with light rain.

Snowpack Summary

Convective flurries over the past week have added to the storm slab, with 30-50cm overlying a crust on solar aspects. Persistent weak layers from February are down 70-120cm and are of most concern on solar aspects. On northerly aspects the snowpack has less layers of concern, although on lee features in the alpine buried wind slabs may exist.

Avalanche Summary

Artillery avalanche control procured several size 1.5 to 2.0 avalanches and one large size 3.0 avalanche. 3 size 2.0 natural avalanches were observed in the highway corridor.

Confidence

Timing or intensity of solar radiation is uncertain

Problems

Storm Slabs

A 30-50cm deep storm slab has formed. It is expected to become increasingly reactive due to the strong solar. In addition, on solar aspects it overlies a sun crust which provides a sliding surface. On lee features, watch for touchy wind slabs.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Use caution in lee areas. Recent wind loading have created wind slabs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

Tests, and recent avalanches in the region, continue to show that a layer down 75 to 100 is triggerable by light loads (that's you). If triggered this layer is likely to propagate into large avalanches. This layer is of most concern on solar aspects.

Choose well supported terrain without convexities.Minimize exposure to steep, planer south facing Alpine slopes

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Cornices

Large cornices exist on many ridges. Rapid changes, from very cold overnight to being beat on by strong solar may cause them to fail. A falling cornice is likely to trigger deeper layers and cause large avalanches.

Do not travel on slopes that are exposed to cornices overhead.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

2 - 3

Valid until: Mar 19th, 2016 8:00AM