Archived

Avalanche Forecast

Apr 12th, 2017–Apr 13th, 2017

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Glacier.

Watch the rising temperatures today an it's affect on the snow. Evaluate each slope independently and keep your eyes up for overhead hazards.

Weather Forecast

Clouds rolling in this morning and precipitation starting this afternoon. We're expecting 5cm of snow above 1700m, light rain below and winds will be moderate from the east. 35mm of total precip is forecasted to fall by Friday, then we should see a high pressure build in for the weekend lasting until Tuesday.

Snowpack Summary

At treeline and above over 45cm of snow has fallen in the last 6 days, amounts decrease with elevation. The new snow is settling and overlies a firm crust everywhere except high elevation N'ly aspects. Strong S'ly winds loaded lee features over the weekend. Cool temps overnight are providing crust recoveries, stabilizing lower elevations.

Avalanche Summary

Strong solar yesterday afternoon triggered loose moist avalanches to size two below tree line. Older storm slabs were most reactive on solar asp where a crust exists down ~45cm. In addition a few large cornice failures were observed from N'ly aspects and small, thin windslabs have been reported in the alpine.

Confidence

Due to the number and quality of field observations

Avalanche Problems

Storm Slabs

Storm slabs are most volatile where they overlie a crust on solar aspects. Recent wind loading has redistributed the storm snow, leaving behind isolated pockets of wind slabs. lower elev should have seen a crust recovery last night.

Choose well supported terrain without convexities.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Cornices

Cornices are always unpredictable! However we are seen cornices fail in the HWY corridor and in the back country on a semi regular basis. With minimal natural triggers today, back country enthusiasts would be the likely trigger.

Stay well to the windward side of corniced ridges.Minimize exposure to overhead hazard from cornices.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 3