Avalanche Forecast

Issued: Mar 5th, 2023 4:00PM

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

Avalanche Canada trettie, Avalanche Canada

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Continually monitor conditions as you move through terrain.

There is a lot to keep in mind; the likelihood of triggering slab avalanches will increase if solar input occurs, wind slabs could be found on all aspects and there is some uncertainty in distribution of the persistent slab problem.

If in doubt choose simple terrain.

Summary

Confidence

Moderate

Avalanche Summary

Over the past few days several skier triggered avalanches up to size 2.5 have been reported. many of these avalanches failed on weak layers from February and January and occurred at treeline. a few skier triggered wind slabs have also been reported , these avalanches have been near ridge crests on north and east aspects.

Check out this MIN from Saturday showcasing the current wind slab problem.

Snowpack Summary

Storm totals from the past week average 40 to 60 cm. Expect to find wind slabs on all aspects due to shifting wind direction. This storm snow sits over heavily wind affected surfaces at all elevations.

A layer of surface hoar can be found on shaded slopes, and a sun crust on sun affected slopes buried 40 to 70 cm deep. Another layer from January is buried up to 50 cm below this. These layers has been noted as a failure plane for some avalanche activity.

Otherwise, the snowpack is generally well consolidated and bonding. The lower snowpack includes a layer of weak sugary crystals near the ground. These facets are slowly gaining strength and have not produced recent avalanche activity. We continue to track the layer and watch for any signs that it could wake up and produce very large avalanches.

Weather Summary

Sunday Night

Mostly cloudy with the possibility of light flurries bringing a few centimeters of new snow. Moderate southeast winds shifting to light southwest. Low of -12°C at 1800 m.

Monday

A mix of sun and cloud with the possibility of light flurries bringing a few centimeters of new snow. Light southwest winds and a high of -5°C at 1800 m.

Tuesday

Mostly sunny with the possibility of light flurries bringing trace amounts of new snow. Light variable winds and a high of -4°C at 1800 m.

Wednesday

Mostly sunny with no new snow expected. Light to moderate southeast winds and a high of -4°C at 1800 m

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Keep in mind that human triggering potential persists as natural avalanching tapers off.
  • Persistent slabs have potential to pull back to lower angle terrain.
  • Surface hoar distribution is highly variable. Avoid generalizing your observations.
  • Avoid avalanche terrain during periods of strong sun.

Problems

Wind Slabs

An icon showing Wind Slabs

Variable winds over the past few days mean that wind slabs could be found on all aspects. Periods of strong winds may have formed wind slabs further down slope than usual.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

There are two layers of concern in the upper and mid pack. These layers are generally made up of facets and surface hoar but on south aspects a crust can be found. These layers are most likely to be triggered on sparsely treed slopes at treeline and below.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Mar 6th, 2023 4:00PM