Avalanche Forecast

Issued: Mar 12th, 2023 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 trettie, Avalanche Canada

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Keep an eye out for blowing snow. If the wind picks up new reactive wind slabs could form. New wind slabs on northerly aspects could form over surface hoar making them more reactive.

Summary

Confidence

Moderate

Avalanche Summary

Wind slabs have been naturally and human triggered to size 2 over the past few days. With fresh snow expected overnight and tomorrow throughout the day new wind slabs could form if the winds pick up.

Snowpack Summary

Surface conditions are a mix of very wind affected snow in exposed terrain features, wind slabs, sun crust on all solar aspects, and preserved softer snow with very large surface hoar on top in sheltered areas.

This MIN does a good job summarizing surface conditions.

A layer of surface hoar buried in early March is down 10 to 30 cm at treeline and below on shaded slopes.

Another layer of small surface hoar or facets is now buried over 80 cm deep. A facet/crust layer formed in late January exists around 150 cm deep. Large avalanches were suspected to have run on this layer in mid February. Triggering these deeper layers may still be possible for large loads in places where the snowpack is shallow.

The lower snowpack is generally well consolidated but the snowpack becomes thinner and weaker near the ground as you move further inland.

Weather Summary

Sunday Night

Cloudy with up to 5 cm of new snow expected. Light easterly winds at ridge tops and continued moderate outflow winds at valley bottoms. A low of -8°C at 1500 m.

Monday

Cloudy with 5 to 10cm of new snow expected. Light southerly winds and outflow easing throughout the day. A high of -6°C at 1500 m.

Tuesday

Cloudy with 5 to 10 cm of new snow expected. Light southerly winds and a high of -5°C at 1500 m.

Wednesday

Cloudy with 5 to 15 cm of new snow expected. Moderate southwest winds and a high of -6°C at 1500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Seek out sheltered terrain where new snow hasn't been wind-affected.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Wind Slabs

An icon showing Wind Slabs

Previous north and east winds have formed wind slabs on south and west facing slopes. As new snow arrives and the winds shift to the south it is possible that new wind slabs could form.

New wind slabs could form over surface hoar making them more sensitive to rider traffic.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 13th, 2023 4:00PM