Avalanche Forecast

Issued: Apr 15th, 2022 4:00PM

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

Avalanche Canada dsaly, Avalanche Canada

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Be mindful of hazards from wind slabs and cornices. Check out the newest forecaster blog as you plan your spring objectives. 

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

FRIDAY NIGHT: Clear. Alpine temperature drops to -14 C. 10-25 km/h winds from the east.

SATURDAY: Sunny. Freezing level rises to 1000 m, alpine temperature rises to +1 C. 5-15 km/h winds from the south. 

SUNDAY: Sunny. Alpine temperature rises to +2 C. 10-30 km/h winds from the south.

MONDAY: Increasing cloud and incoming flurries. Alpine temperatures rises to +3 C, freezing level rising above 1600 m. Southeast wind increasing to 60 km/h.

Avalanche Summary

On Thursday, explosives triggered wind slabs size 1-2 on south-southeast aspects. A skier triggered a size 1 wind slab on a northwest aspect at 1700 m. Additionally, a vary large (size 3.5) natural cornice failure triggered a deep slab on the steep slope below which ran full path. On Wednesday in the north of the region, several natural wind slabs (size 1.5-2) were observed in the alpine as a result of strong outflow winds loading west-facing aspects. One natural cornice failure was also observed (size 2.5) that did not pull a slab on the slope below.

Numerous natural wind slabs (size 2-3) were observed in the alpine on Monday and Tuesday as a result of northeasterly outflow winds. These wind slabs mainly occurred on west-facing slopes. Looking forward, wind slabs may still exist in lee areas in the alpine and exposed treeline. Riders should minimize overhead exposure to cornices and give them a wide berth when travelling at ridge crest. 

Snowpack Summary

Open terrain has been affected by strong outflow wind that has scoured east-facing slopes and loaded snow onto west-facing slopes. Sheltered areas may still have soft snow. Below 1200 m, a widespread crust exists on the surface. Above 1200 m, 40 to 80 cm of settled storm snow rests on a hard melt-freeze crust from late March. The snow has been bonding to this crust.

Terrain and Travel

  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Back off slopes as the surface becomes moist or wet with rising temperatures.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent outflow wind has left slabs on west and south-facing slopes in the alpine and near ridgetops at treeline. These slabs could remain reactive to human triggering for a few more days.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Cornices

An icon showing Cornices

Cornices are large this time of year and may have been weakened by recent cold temperatures. Exposure to cornices should be minimized, especially during periods of warm temperatures or strong sun. Give them a wide berth when you are travelling on ridge lines and avoid overhead exposure to large cornices. 

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Apr 16th, 2022 4:00PM