Avalanche Forecast

Issued: Dec 13th, 2012 8:00AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Loose Dry and Persistent Slabs.

Parks Canada sylvia forest, Parks Canada

Rogers Pass is still providing good skiing conditions.  Just watch out for those pockets of slab which could pop out unexpectedly, and be careful of early season hazards like stumps and rocks.  If traveling on glaciers, be aware of thin snow bridges.

Summary

Weather Forecast

Very little snowfall is in the forecast for the next couple of days.  Mild temperatures, light winds and some convective activity can be expected today, and dryer conditions for Friday.  More precipitation is expected (up to 12 mm) on Saturday.

Snowpack Summary

Recent storm snow has developed into a wind slab in the alpine, and rests on a well settled mid-pack.  The Nov. 28 and Nov. 16 crust-surface hoar layers, and the Nov. 6 crust can all be found in profiles, but are not very reactive in tests.  There is substantial variation in snow depth depending on elevation and aspect.

Avalanche Summary

Very little avalanche activity has been observed in the past few days.  Avalanches which have been observed are mostly from steep alpine start zones affected by wind.  Wind affected and cross loaded features, and thin areas are most likely to produce human triggered avalanches.  Some loose snow sluffing has also been observed in steep terrain.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Wind Slabs

An icon showing Wind Slabs
Near ridge line, pockets of wind slab persist, and may be triggered by riders. Cross loaded features and gullies should also be treated with caution.
Be careful with wind loaded pocketsAvoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Dry

An icon showing Loose Dry
With an additional 10-15cm of very light snow, sluffing is possible where the wind has had no effect. Caution skiing in steep terrain and over terrain traps where sluffs will gain mass into avalanches.
Avoid travelling under cliffs that are exposed to sluffing from above.Sluffs may trigger deeper instabilities.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs
The Nov 6 crust complex has yet to wake up. While the likelihood of triggering is low, it will produce large avalanches. As the load on this layer increases, it may become reactive. Smaller avalanches may step down to this deeper layer.
Pay attention to overhead hazards like cornices.The snowpack on glaciers is shallow, and the use of a rope is recommended.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Dec 14th, 2012 8:00AM