Archived

Avalanche Forecast

Jan 8th, 2013–Jan 9th, 2013

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

2: Moderate

The avalanche danger rating below treeline will be moderate

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

2: Moderate

The avalanche danger rating below treeline will be moderate

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

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Northwest Inland.

Confidence

Fair - Timing, track, or intensity of incoming weather is uncertain on Wednesday

Weather Forecast

Wednesday: Moderate NE wind. Alpine temperature near -10. No precipitation.Thursday: Moderate NW winds. Alpine temperature near -12. Light snow.Friday: Light W wind. Alpine temperature near -9. 8-12 cm snow.

Avalanche Summary

Snowmobilers witnessed naturally-triggered slabs and loose dry sluffs in the Seaton Basin on Monday.

Snowpack Summary

New snow is building up over a weak, faceted old snow surface, which may lead to storm slab development or loose dry sluffing. In wind-affected areas, wind slabs have formed behind terrain breaks such as ridges and ribs. A strong mid-pack overlies a weak base layer of facets and the remnants of a crust. As snow builds up incrementally over these weaknesses, avalanche danger is also likely to gradually increase. Under these circumstances, it can be hard to evaluate if/when the tipping point will occur which leads to slab avalanches failing on persistent weak layers. Keep track of snow loading in your local area and adopt a cautious approach to terrain selection.

Avalanche Problems

Storm Slabs

Soft storm slabs are slowly developing with daily snow falls combined with moderate shifting winds.

Avoid freshly wind loaded features.>Be cautious as you transition into wind affected terrain.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Deep Persistent Slabs

A deeply buried facet/crust weakness exists near the base of the snowpack. This layer could be triggered by large loads such as a cornice collapse or from a thin-spot trigger point.

Be aware of thin areas that may propagate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 5