Avalanche Forecast

Issued: Feb 4th, 2023 2:30PM

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

Avalanche Canada jpgagnon, Avalanche Canada

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The wind will abate for Sunday BUT NOT the probability of triggering freshly formed wind slabs.

Summary

Confidence

Moderate

Avalanche Summary

No observations could be made in the last few days by our team due to bad weather. No new avalanche was reported since Thursday.

Thanks for contributing to the collection of this valuable data by sharing with other users on the Mountain Information Network or by writing to us directly at bulletin@avalanchequebec.ca.

Snowpack Summary

About 15 to 20 cm of storm snow has been added since Thursday evening to the 15 to 20 cm of very light snow already present on the January 18 crust or on a slightly denser layer covering the latter. With the extreme westerly wind that blew for 2 days, a good part of this snow was moved into the alpine and at treeline forming new wind slabs. A great deal of spatial variability is thus present in the alpine and at the treeline, from windy slabs to wind-affected snow or to ice or rock. Facets are developing over the January 18 crust and have demonstrated some weaknesses in our tests.In general, the height of the snowpack varies from 70 to 90 cm in the valley to 100 to 150 cm at mid-mountain.

Weather Summary

Forecast for the Chic-Chocs ridges and summits.

Synopsis: A weak low pressure system moving in from the north will pass over the area on Sunday followed by a high pressure system on Monday and Tuesday.

Saturday night and overnight: Light snow showers. Extreme northwest wind diminishing to 20 to 40 km/h late in the night. Low -29.

Sunday: Light intermittent snow beginning in the afternoon (1 to 2 cm). Wind southwest 25 to 50 kph. High -16.

Monday: Alternating sun and clouds. Wind northwest 15 to 30 kph. High -14.

Tuesday: Sunny. Wind southeast 30 to 50 kph. High -12.

For more details, check the Alpine Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

Problems

Wind Slabs

An icon showing Wind Slabs

Significant new wind slabs are likely to occur on leeward slopes and in cross loaded locations of the alpine and treeline. They may rest on other unstable slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

With the cold temperatures, facetted grains developed on and under the January 18 ice crust. We have been getting regular test results showing avalanche triggering potential for the past few days. As with any persistent slab problem, the problem is very sporadic, almost isolated and the spatial variability is significant. It is therefore possible to test a few meters away and get a completely different results on this crust. The probabilities of triggering are low, but the consequences could be very unfortunate. The problem seems to be a little more important at the treeline, where the snowpack is thinner, near natural obstacles, such as trees or rocks.

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

Elevations: Treeline, Below Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Feb 5th, 2023 3:00PM