Avalanche Forecast

Issued: Dec 15th, 2017 4:31PM

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

jsmith, Avalanche Canada

South Columbia.

Isolated small wind slabs may have formed below ridgetops in areas that received 10cm or more of snow on Friday.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

SATURDAY: Mix of sun and cloud / Light northwesterly ridgetop winds / Freezing level valley bottom.SUNDAY: 10-15cm snow / Moderate to strong westerly ridgetop winds / Freezing level valley bottom.MONDAY: Mostly cloudy / Light westerly ridgetop winds / Freezing level valley bottom.

Avalanche Summary

No new avalanches were reported within this region on Thursday. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

The 5-10cm of new snow on Friday fell on a wide variety of surfaces including large surface hoar (weak, feather-like crystals), hard crusts formed by sun or wind, and sugary facets. There is not yet significant new snow load to create big problems, however, it will be important to monitor how the new snow is bonding to the smorgasbord of surfaces out there. When we receive significant new snow and it settles into a cohesive slab, you can bet there will be avalanches. I would be most concerned about areas that have surface hoar sitting on top of a hard crust. A major feature in the snowpack is a crust which was formed by rain in late November. It is down approximately 40-80cm at treeline elevations and snowpack tests suggest the snow is currently bonding well to it.Below treeline, the snowpack depth decreases rapidly. Look out for early season hazards such as rocks, stumps, and open creeks.

Problems

Wind Slabs

5-10cm of new snow on Friday combined with light to moderate winds from a variety of directions may have formed small wind slabs in isolated locations below ridgetops.

Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Loose Dry

Only a problem in steep terrain that received 10cm or more of new snow.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Dec 16th, 2017 2:00PM