Archived

Avalanche Forecast

Mar 27th, 2013–Mar 28th, 2013

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

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

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

Regions: South Coast.

Avalanche Danger will increase with daytime heating on south and west facing terrain. Be aware of changing conditions.

Confidence

Good

Weather Forecast

Thursday: There is a slight chance of thin cloud developing with isolated flurries. Winds should be calm with alpine temperatures reaching 2.Friday & Saturday: Expect mostly clear skies, light southerly winds and alpine temperatures reaching 5 in the afternoons.

Avalanche Summary

Loose wet avalanches up to 2.0 have been reported on solar aspects.

Snowpack Summary

Recent warm temperatures have created melt freeze crusts up to 2000m on all aspects and well into the alpine on south and west facing terrain. These crusts break down with daytime warming and the surface snow can lose cohesion as a result. Cornices are huge!Various melt-freeze crusts are buried in the upper snowpack. In general, the bond at these interfaces is good. A layer of surface hoar (buried on March 11; now down about 60 cm) is still being observed in some locations, with moderate to hard results in snowpack tests. Triggering this layer has become less likely, but possible with a large trigger or from a thin snowpack zone. Mid and lower snowpack layers are well bonded.

Avalanche Problems

Loose Wet

Daytime warming or solar radiation may cause loose wet avalanches on steep south-facing or low elevation slopes. Wet slabs are also possible, especially on steep low elevation terrain.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Watch for glide cracks.>

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

Elevations: All elevations.

Likelihood: Likely - Very Likely

Expected Size: 1 - 4

Cornices

Cornices are large and lose strength with daytime heating.

Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 6

Persistent Slabs

Avalanches failing on a crust and/or surface hoar layer buried about 60 cm are becoming less likely, but could be triggered with a heavy load (cornice), or from a thin or convex-shaped part of a slope.

Be cautious of convexities or areas with a thin or variable snowpack.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 6