Archived

Avalanche Forecast

Dec 5th, 2013–Dec 6th, 2013

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

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.

This forecast is based on limited field observations. If you head into the mountains, please send a note to forecaster@avalanche.ca and let us know what you saw.

Confidence

Poor - Due to the number of field observations

Weather Forecast

Synopsis: An arctic ridge of high pressure will persist over the BC Interior and Yukon for the next several days. Friday: Mainly sunny with moderate northerly alpine winds. Treeline temperatures expected to be around -20. Saturday: Mainly sunny with some thin cloud possible, moderate northwesterly alpine winds. Treeline temperatures expected to be around -20. Sunday: Increased cloud, windy, and cold.

Avalanche Summary

No recent avalanches have been reported but incoming field data is still very limited. Avalanche activity in the neighbouring Monashee Mtns seems to be slowing down.

Snowpack Summary

30-50 cm of recent storm snow overlies a variety of old snow surfaces including surface hoar in sheltered areas and/or sun crust on steep south facing slopes. In some neighbouring areas the buried surface hoar is giving easy to moderate sudden planar compression test results, while elsewhere the storm snow has yet to settle into a sufficiently cohesive slab. There are two distinct weaknesses within the mid and lower snowpack: the early November surface hoar/facet/crust interface is down roughly half way (50-60cm) and the October rain crust is near the ground. Recent snowpack tests gave easy results on the early November mid-pack interface where it was found to be facets under a crust. Cold clear weather is likely promoting surface hoar growth and near surface faceting.

Avalanche Problems

Wind Slabs

Outflow winds are reverse-loading and cross-loading exposed slopes forming fresh and touchy wind slabs below ridge crests and behind terrain features. Don't let wind slabs in unusual places catch you by surprise.

Avoid freshly wind loaded features.>Avoid traveling in areas that have been reverse-loaded or cross-loaded by winds.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 4

Persistent Slabs

Managing these persistent slabs can be tricky; they are stubborn and direct evidence of unstable snow may be lacking, but they can produce very destructive avalanches. Treat large open slopes with suspicion until stability is confirmed.

Use extra caution in areas with a thin or variable snowpack.>Use extra caution around convexities or large unsupported slopes.>Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.>Dig down to find and test weak layers before committing to a line.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 2 - 5