Avalanche Forecast

Issued: Nov 28th, 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.

Avalanche Canada ghelgeson, Avalanche Canada

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Last week's snow has been formed into wind slabs at upper elevations which may be sensitive to human triggering. Watch for wind slabs in the alpine and "alpine like" features at treeline.  

Summary

Confidence

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

Weather Forecast

The weather forecast is rather unexciting for the Lizard/Flathead zone over the next few days.

SATURDAY NIGHT: Freezing level at valley bottom, light southwest wind, no precipitation expected. 

SUNDAY: Clear skies, light to moderate west/southwest wind, freezing level rising to between 1000 and 1500 m, no precipitation expected. 

MONDAY: Clear skies at dawn with increasing cloud cover building in after lunch, light to moderate southwest wind, freezing level rising to about 1000 m, no significant precipitation expected. 

TUESDAY: Scattered cloud cover, freezing level around valley bottom, light southwest wind, no precipitation expected. 

Avalanche Summary

Observations are limited right now, but there have been no reports of recent avalanches. 

We appreciate the recent reports submitted to the Mountain Information Network. Keep them coming!

Snowpack Summary

Wind slabs have formed in open terrain as last weeks 10 to 20 cm of snow is redistributed and formed into more cohesive slabs. These slabs may sit above a layer of surface hoar in sheltered terrain and above a hard crust in other areas. 

Snowpack depths at upper treeline elevations are nearing 100 cm and beginning to exceed the threshold for avalanches, while the snowpack is much thinner in the valleys. 

The lower snowpack consists of crusts. Weak snow may be developing around these crusts in some areas, which will be a snowpack feature to monitor as the season progresses.

Terrain and Travel

  • Avoid areas where the snow feels stiff and/or slabby.
  • Avoid freshly wind loaded terrain features.
  • Watch for signs of slab formation throughout the day.

Problems

Wind Slabs

An icon showing Wind Slabs

Watch for freshly formed wind slabs in the alpine, and "alpine like" features at treeline. These slabs may be poorly bonded to underlying crust and surface hoar layers, although the distribution of these layers is uncertain.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Nov 29th, 2020 4:00PM

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