Avalanche Forecast

Issued: Nov 27th, 2020 4:00PM

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

Avalanche Canada JSmith, Avalanche Canada

  

Check out this notable skier triggered avalanche from Quartz Creek on Thursday. Although the danger rating may be “Moderate”, the recently buried layer of small surface hoar that caused this avalanche could likely catch riders by surprise this weekend! 

Summary

Confidence

Low - Uncertainty is due to the limited number of field observations.

Weather Forecast

  

FRIDAY NIGHT: Cloudy w/ flurries; 0-3 cm. / Moderate, southwest wind / alpine low temperature -9 / Freezing level 1000 m.

 SATURDAY: Mix of sun and cloud / Light, southwest wind / alpine high temperature -4 / Freezing level 1000 m.

 SUNDAY: Mix of sun and cloud / Light, southwest wind / alpine high temperature -6 / Freezing level 900 m.

 MONDAY: Cloudy w/ flurries; 3-5 cm. / Moderate, northwest wind / alpine high temperature -4 / Freezing level 1000 m.

Avalanche Summary

Check out this notable skier triggered avalanche from Quartz Creek on Thursday. The recently buried layer of small surface hoar that caused this avalanche could likely catch riders by surprise this weekend!

In the past week there have been a few size 2 avalanches reported on the early November crust. These have been triggered by both humans and explosives.

If you get out into the mountains, please consider sharing your observations on the Mountain Information Network!

Snowpack Summary

  

Recent strong southwest winds have created fresh wind slabs on lee features at treeline and above. There have been a couple human triggered avalanches on a recently buried layer of small surface hoar. This layer has been reported as "spotty" and is most likely to be present in sheltered areas. There is a crust from early November that is down approximately 50-75 cm. This layer has been observed to have weak, sugary facets above and below it. Recent observations of this layer indicate that it has the potential to be human triggered.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • In times of uncertainty conservative terrain choices are our best defense.
  • Closely monitor how the new snow is bonding to the old surface.
  • Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

Problems

Wind Slabs

An icon showing Wind Slabs

 Recent strong southwest winds have created fresh wind slabs on lee features at treeline and above.  

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A crust from early November exists down about 50-75 cm. This layer has weak, sugary facets above and below it. Recent observations suggest that it has the potential to be human triggered.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Nov 28th, 2020 4:00PM