Avalanche Forecast

Issued: Feb 1st, 2021 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs and Persistent Slabs.

Avalanche Canada JSmith, Avalanche Canada

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Touchy storm slabs are sitting on a very weak layer of surface hoar which is very likely to be reactive to human triggers, even in low angle terrain. Avalanches may be larger than expected due to the presence of this weak layer.

Summary

Confidence

Moderate - Uncertainty is due to the timing, track, & intensity of the incoming weather system. Uncertainty is due to the limited number of field observations.

Weather Forecast

  

MONDAY NIGHT: Snow; 15-20 cm. / Strong, south ridgetop wind / alpine low temperature -7 / Freezing level valley bottom.

TUESDAY: Snow; 5-10 cm. / Moderate, southwest ridgetop wind / alpine high temperature -5 / Freezing level valley bottom.

WEDNESDAY: Mostly cloudy with sunny periods / Moderate, northwest ridgetop wind / alpine high temperature -10 / Freezing level valley bottom.

THURSDAY: Snow; 5-10 cm. / Strong, west ridgetop wind / alpine high temperature -9 / Freezing level valley bottom.

Avalanche Summary

Touchy storm slabs are sitting on a very weak layer of surface hoar which is very likely to be reactive to human triggers, even in low angle terrain. Avalanches may be larger than expected due to the presence of this weak layer.

A MIN report from just outside this region in Clemina Creek likely represents the surface hoar layer of concern that we suspect is present in much of the Cariboos. Report HERE.

Note: We currently have very few observations from this region. Please consider sharing what you see by submitting a MIN report.

Snowpack Summary

25-30 cm of new snow as of Monday afternoon brings recent snow totals up to 40 cm. Touchy storm slabs are sitting on a weak layer of surface hoar which has potential to surprise backcountry users by how easily these storm slabs may be triggered and how wide the slabs propagate across slopes.

A second weak of layer of surface hoar and crust from early January is 50-110 cm deep and tapers above 1700 m. This layer was last reactive almost 2 weeks ago (Jan 16) in the south of the region near Valemount. It is most suspect in sheltered, open slopes at and below treeline. Deeper in the snowpack, a couple of older persistent weak layers may still be identifiable from late and early December, consisting of surface hoar and a crust with faceted snow and buried anywhere from 70-150 cm deep. Deeper layers may wake up with heavy snow fall and warm temperatures.

Terrain and Travel

  • Keep in mind that human triggering potential persists as natural avalanching tapers off.
  • Be aware of the potential for large avalanches due to the presence of buried surface hoar.
  • Good day to make conservative terrain choices.
  • Be aware of the potential for human triggerable storm slabs at lower elevations, even on small features.
  • Avoid traveling through runout zones during stormy periods when large avalanches are likely.

Problems

Storm Slabs

An icon showing Storm Slabs

Touchy storm slabs are sitting on a very weak layer of surface hoar which is very likely to be reactive to human triggers, even in low angle terrain. Avalanches may be larger than expected due to the presence of this weak layer.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

New snow loads have potential to awaken deeply buried weak layers.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Feb 2nd, 2021 4:00PM