Avalanche Forecast

Issued: Mar 22nd, 2017 4:26PM

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

mbender, Avalanche Canada

South Coast Inland.

Snowfall amounts over the coming days vary between the north and south portions of the region. Light to moderate amounts of snow accompanied by wind will gradually raise danger ratings.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Friday

Weather Forecast

THURSDAY: Â Flurries, accumulation 5cm / Moderate to strong south wind / Alpine temperature -2 / Freezing level 1300mFRIDAY: Flurries, accumulation 10-15cm / Moderate to strong southwest wind / Alpine temperature -3 / Freezing level 1400mSATURDAY: Flurries, accumulation 5cm / Moderate southwest wind / Alpine temperature -4 / Freezing level 1000m

Avalanche Summary

There is no recent avalanche activity to report. On Thursday, wind slabs may remain reactive to human triggers at upper elevations. In northern parts of the region, the deeper February weak layers continue to present a low probability / high consequence scenario.

Snowpack Summary

On Tuesday the freezing level reached 2000+m. A subsequent freezing may have created a thin crust. 10-15cm of snow at upper elevations may now sit on this crust. Thicker wind slabs and large cornices likely exist in alpine terrain. A widespread thick rain crust forming last week up to 2100m is now approximately 40-60cm below the surface. In the north of the region, the February weak layers are 80-120 cm deep and include a buried surface hoar layer that recently produced a few persistent slab avalanches and a crust/facet layer that appears to be gaining strength. In the southern parts of the region, the lower snowpack is generally stable.

Problems

Wind Slabs

New snow combined with moderate to strong southwesterly winds will have created new reactive wind slabs in the lee of alpine and tree line terrain features

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.Extra caution needed around cornices with current conditions.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Heavy triggers such as a cornice fall or a small avalanche could potentially step down to weak layers buried about 1 m deep in the northern parts of the region.

Pay attention to overhead hazards like cornices which could trigger persistent slabs.If triggered, wind/storm slabs may step down to deeper layers resulting in very large avalanches.Carefully evaluate and use caution around thin snowpack areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Mar 23rd, 2017 2:00PM