Avalanche Forecast

Issued: Mar 30th, 2022 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Cornices and Loose Wet.

Avalanche Canada zryan, Avalanche Canada

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Cautious route-finding will be important at upper elevations as fresh wind slabs are likely to trigger.

If the sun comes out, wet loose avalanches may occur in steep terrain. Be aware of what is above you, and avoid exposure to steep slopes and cornices baking in the sun

Summary

Confidence

Moderate - Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.

Weather Forecast

WEDNESDAY NIGHT: Cloudy with flurries. Freezing level dropping to 500 m. 20-50km/h westerly winds at ridge top.

THURSDAY: Mainly cloudy with scattered flurries, light accumulation. Freezing level rising to 1300 m. 15-40 km/h westerly winds. 

FRIDAY: Cloudy with isolated flurries. Light southwesterly winds increase to 30-50 km/h in the afternoon. Freezing level rising to 1400 m.

SATURDAY: Scattered cloud cover. 15-30 km/h southwesterly winds. Freezing level rising to 1500 m.

Avalanche Summary

Several small (size 1) wet loose avalanches were observed in the Kakwa on Tuesday out of steep terrain as a result of warm temperatures and strong solar radiation.

On Monday, a size 1.5 skier-triggered wind slab occurred on south aspect at treeline. This wind slab failed on a slick crust below the new snow. 

Snowpack Summary

5-15 cm of new snow overlies 20 cm of denser snow that tapers rapidly with elevation. Westerly winds have formed small pockets of windslab in the alpine and exposed treeline. A crust or moist snow can be found below the new snow on all aspects as high as 2000 m and to mountain top on solar aspects. Below the crust, the top 10-30 cm of the snowpack is moist.

There are no deeper concerns at this time.

Terrain and Travel

  • Cornices become weak with daytime heating or solar exposure.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs can be expected in lee terrain features in the alpine and treeline, formed by recent snowfall and westerly winds. These wind slabs will be most reactive where they overlie a slick crust.  

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Cornices

An icon showing Cornices

Springtime cornices are large and unpredictable. Give them a wide berth when travelling at ridge crest and avoid overhead exposure, especially when the air temperature is warm or solar radiation is strong.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3

Loose Wet

An icon showing Loose Wet

If the sun comes out on Thursday, wet loose activity can be expected on steep solar aspects at all elevations. Watch for wet and heavy snow conditions.

Aspects: South East, South, South West, West.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 31st, 2022 4:00PM