Archived

Avalanche Forecast

Apr 9th, 2017–Apr 10th, 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

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

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

1: Low

The avalanche danger rating below treeline will be low

Regions: South Coast.

Yesterday's avalanche accident near Lions Bay highlights that it's still winter at higher elevations.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

MONDAY: Overcast sky with another 10 or 15 cm of snow at high elevations overnight Sunday and into Monday morning. Alpine and Treeline temperatures from a couple of degrees below freezing to a couple of degress above freezing. Freezing level around 900 m. Light to Moderate southerly windsTUESDAY: Mix of sun & cloud with a trace of precipitation. Termperatures at Treeline between -3 and +3 C with freezing level near 1500m. Light southeast or east winds.WEDNESDAY: Overcast with around 15 cm of snow at higher elevations but rain down lower. Similar temperatures (as cold as -5C and as warm as +2C) and freezing level (around 1600m). Moderate SE wind.

Avalanche Summary

On Monday the main concern is wind slab avalanches where the recent precipitation fell as snow and was drifted by the wind behind ridges. At tree line expect small loose wet avalanches in steep terrain. Saturday's fatal avalanche on Mt Harvey (near Lion's Bay) was the result of people being on a cornice that broke.

Snowpack Summary

Saturday's cold stormy weather brought snow to the mountains as low as 800m. It's still winter up high! Sunday was a calmer and dryer day but isolated lingering wind slabs remain a concern. At lower elevations, rain has saturated an already wet snowpack.

Avalanche Problems

Wind Slabs

Warm temperatures should help recent snow bond and settle in place; however, isolated wind slabs may linger.

Be cautious as you transition into wind affected terrain.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2

Loose Wet

Rain at lower elevations has led to a gradual break down of surface crusts and has contributed to wet snow sluffing and gathering mass in steep terrain.

Use caution above cliffs and terrain traps where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2