Avalanche Forecast

Issued: Apr 22nd, 2023 4:00PM

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

Avalanche Canada jsmith, Avalanche Canada

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Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Concern for triggering large persistent slab avalanches remains. Avoid steep, rocky, and wind affected areas where triggering slabs is more likely.

Summary

Confidence

Low

Avalanche Summary

No avalanches were reported on Friday. However, observations in this region are currently very limited.

A few naturally triggered size 2 wind slab avalanches were reported on steep, northerly aspects in the alpine on Thursday.

Most professional operations are now closed which means we have very little snowpack or avalanche observation data. Please consider sharing any information or photos you have on the Mountain Information Network to help guide our forecasts.

Snowpack Summary

New snow and strong southerly wind may have formed wind slabs on lee aspects at treeline and above.

A crust exists up to ridgetop on south-facing slopes and on all aspects up to approximately 1300 m.

A weak layer buried in late March is down 40-60 cm and exists as surface hoar and facets on north-facing slopes and a crust elsewhere.

The mid and lower snowpack is considered generally strong and well-bonded.

Weather Summary

Saturday Night

Cloudy with flurries; 3-20 cm (rain below 900 m) / 40 km/h south ridgetop wind / Temperature at treeline around -2 C / Freezing level 1000 m

Sunday

Cloudy with isolated flurries; 0-10 cm (rain below 1000 m) / 40 km/h south ridgetop wind / Temperature at treeline around -1 C / Freezing level 1200 m

Monday

Cloudy with isolated flurries; 3-5 cm / 50 km/h southwest ridgetop wind / Temperature at treeline around -2 C / Freezing level 1100 m

Tuesday

Cloudy with isolated flurries; 0-3 cm / 40 km/h southwest ridgetop wind / Temperature at treeline around -3 C / Freezing level 1000 m

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

New snow and strong southerly wind may have formed wind slabs on lee aspects at treeline and above.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A weak layer buried in late March is down 40-60 cm and exists as surface hoar and facets on north-facing slopes and a crust elsewhere.

We currently have very limited snowpack observations from this region to aid in determining the likelihood of triggering avalanches on the layer.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 3

Valid until: Apr 23rd, 2023 4:00PM