Avalanche Forecast

Issued: Mar 9th, 2023 4:00PM

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

Avalanche Canada lbaker, Avalanche Canada

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Diligently maintain a conservative mindset. You may not see signs of instability on the surface however the deep persistent weak layer remains a major concern at the bottom of the snowpack.

Avoid shallow rocky terrain where the snowpack transitions from thick to thin and triggering the deep persistent layer is more likely.

Summary

Confidence

Moderate

Avalanche Summary

No recent avalanches have been reported in this region.

On Tuesday, a deep persistent slab avalanche was triggered by a cornice or solar input in extreme, rocky terrain in the Elkford area. See the MIN for a photo.

Snowpack Summary

Flurries accumulate over 40-50 cm of wind-affected snow in the alpine and open treeline. On solar slopes, they overlie a thin sun crust.

In the Purcells several weak layers from Jan and Feb can be found down 50 to 120 cm however they are showing signs of strengthening. The mid-snowpack is generally well settled.

The lower snowpack is made up of a widespread layer of large, weak basal facets and depth hoar in some areas. this weakness has been responsible for a number of recent very large, destructive avalanches and will continue to be a concern.

Weather Summary

Thursday Night

Increasing cloud through the evening. Southeast winds 15-25 km/h. Treeline temperature low of -12.

Friday

Cloudy with scattered flurries, 2-6 cm accumulation. Southeast ridgetop winds 25-40 km/h. Treeline temperature high of -9.

Overnight flurries continue 1-3 cm accumulation. Winds switch to the west 20 km/h.

Saturday

Cloudy with sunny periods and isolated flurries, trace accumulation. Southwest ridgetop winds 20 km/h. Treeline temperature high of -5.

Sunday

Cloudy with sunny periods and isolated flurries, trace accumulation. Southwest ridgetop winds 20 km/h. Treeline temperature high of -3. Freezing levels rise to 1400 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid areas with a thin or variable snowpack.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The base of the snowpack remains very weak. Very large human triggered avalanches are possible at treeline and above. Avoid shallow and rocky areas, where the snowpack depth is highly variable. This is a very concerning avalanche problem and should stay in your mind when traveling in the backcountry.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Mar 10th, 2023 4:00PM