Avalanche Forecast

Issued: Apr 8th, 2017 5:00PM

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

jsmith, Avalanche Canada

South Rockies.

Cornices are the primary concern. Solar radiation is a common cornice trigger. Limit your exposure when it's cloudy and completely avoid cornices when it's sunny.

Summary

Confidence

High -

Weather Forecast

SUNDAY: Mix of sun and cloud with isolated flurries. Light southwesterly ridgetop winds. Freezing level around 1700 m.MONDAY: Mix of sun and cloud. Light southwesterly ridgetop winds. Freezing level around 1800 m.TUESDAY: Mostly cloudy. Light southwesterly ridgetop winds. Freezing level around 1800 m.

Avalanche Summary

Several loose wet avalanches to size 1.5 were reported in this region on Friday.

Snowpack Summary

10 cm of new snow with strong, southerly winds have created small wind slabs in lee features below alpine ridgetops. A surface crust up to 2300 m. will break down with daytime warming. Cornices remain large, looming, and are best avoided. The snowpack is well settled and continues to transition into a spring snowpack, becoming isothermal at treeline in some areas and below treeline in most areas. The bottom third of the snowpack is composed of weak facets, but this deep persistent weakness has not been reactive for several weeks. However, a large trigger, like a cornice, or rapid warming of the snowpack could potentially trigger this layer.

Problems

Cornices

Solar radiation is a common cornice trigger. Limit your exposure when it's cloudy and completely avoid cornices when it's sunny.

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

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

New snow and moderate southwest winds have formed thin wind slabs below alpine ridgetops.

Avoid freshly wind loaded features.Be alert to conditions that change with elevation.Use ridges or ribs to avoid pockets of wind loaded snow.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Apr 9th, 2017 2:00PM