Archived

Avalanche Forecast

Jan 10th, 2017–Jan 11th, 2017

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

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

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: Cariboos.

Wind effect will drive the avalanche danger in many areas. The safest, and best, riding may be in lower elevation terrain sheltered from the wind.

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Wednesday: Mainly clear skies / Moderate to strong northerly ridgetop winds / Alpine temperatures of -15Thursday: Clear skies / Light and variable winds / Alpine temperatures of -10Friday: Mainly clear skies / Moderate southwest winds / Alpine temperatures of -8

Avalanche Summary

No new avalanches were reported on Monday, although in the neighbouring North Columbia region, wind slab activity to size 1.5 was noted in exposed terrain. Ongoing northerly winds on Tuesday may promote a reverse loading pattern increasing the likelihood of wind slab activity on a variety of aspects.

Snowpack Summary

Up to 36 cm of low density snow fell on Sunday night and Monday. Moderate to strong southwest and then northerly winds have shifted these fresh accumulations into wind slabs at treeline and above. The new snow has also covered old, thicker wind and hard slabs from previous wind events. Persistent and deep persistent weakness in the mid and lower snowpack are giving variable results in snowpack tests, but are expected to be most touchy in shallow snowpack areas. Recent snowpack tests gave moderate but resistant results on facets and/or surface hoar buried mid-December where it was found down 45 cm, and hard but sudden collapse results on the facet/crust weakness buried in November down 116 cm near the base of the snowpack.

Avalanche Problems

Wind Slabs

New snow on Monday was likely shifted by southwest winds into reactive wind slabs in exposed high elevation terrain. On Tuesday, a switch to northerly winds will promote a reverse loading pattern and wind slabs may exist on all aspects.

Be alert to conditions that change with aspect and elevation.Avoid areas where the snow feels stiff or slabby.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Persistent Slabs

Triggering a weak layer of facets and/or surface hoar buried mid-December may still be possible in parts of the region where the snowpack is shallower. Dig down and test for weaknesses before committing to larger terrain features.

Only expose one person at a time to larger slopes.Avoid likely trigger spots such as steep and rocky areas with a shallow snowpack.Choose regroup spots that are out of avalanche terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3