Avalanche Forecast

Issued: Mar 9th, 2023 4:00PM

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

Avalanche Canada PW, Avalanche Canada

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We're still wary of larger features in the backcountry. Everyday this week, we've seen natural activity on the persistent weak layers.

Polar aspects should hold better skiing than sun exposed features at treeline and below.

Summary

Confidence

Moderate

Avalanche Summary

While natural activity has tapered we're still seeing results on the deeper layers of the snow pack. Mt. Norquay ski hill reported a size 3 cornice failure within the last 24 being the most recent.

Likely triggers for natural avalanches are cornice failures and solar radiation and possibly both.

Snowpack Summary

Steep solar slopes at treeline and below are seeing the effects of the sun, with a significant sun crust in places. The various Jan PWL interfaces of sun crusts, facets, and surface hoar are now down 40-80 cm. The weaker Nov. 16 basal facet layer is down 120-170 cm and produces moderate to hard sudden collapse results in tests.

Weather Summary

On Friday we should see the arrival of some snow, with flurries starting in the early afternoon. Southerly regions in the Park could see more snowfall with forecast amounts up 5 cm. Winds will pick up with strong gusts and temperatures will stay cold. An alpine high of -8 is being forecast.

Skies should clear Saturday, with light NW winds and only slightly warmer temperatures.

For a more detailed weather forecast, click here.

Terrain and Travel Advice

  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Uncertainty is best managed through conservative terrain choices at this time.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Weak facets and depth hoar are present at the bottom of the snowpack and inspire little confidence. Be especially cautious in thin snowpack areas, which are likely areas for triggering. Watch for cornice failures triggering this layer, which will be more likely if the sun is out in the afternoon.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3.5

Persistent Slabs

An icon showing Persistent Slabs

Watch the development of wind slabs as the front arrives Friday afternoon. Three persistent weak layers formed in January are down 40-80 cm. The biggest concern is triggering these buried suncrusts on steep solar slopes, but weaker facets and isolated surface hoar can be found at the same interfaces on shaded aspects.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 2.5

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