Avalanche Forecast

Issued: Apr 1st, 2022 4:00PM

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

Avalanche Canada bchristie, Avalanche Canada

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Sea To Sky.

Some fresh snow has us checking for storm slab hazard at all elevations. Snowfall amounts are variable across the region. If you are finding less than 5cm of new snow, the avalanche forecast from yesterday may be more applicable. 

Summary

Confidence

Moderate - The snowpack structure is generally well understood. Uncertainty is due to the track & intensity of the incoming weather system. We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

FRIDAY NIGHT: Cloudy. 3-10 cm of snow expected, possibly more around Squamish. Light southwest ridgetop wind trending to moderate at high elevations. Freezing level falling to around 900 m.

SATURDAY: Mostly cloudy with a sunny break mid-day. Light snowfall expected. Light southwest ridgetop wind trending to moderate west at high elevations. Freezing level rising to 1300 m through the day.

SUNDAY: Mostly cloudy, possible sunny break mid-day. 15-25 cm of snow expected overnight and through the day. Up to 35 cm closer to Squamish. Moderate south ridgetop wind, trending to extreme southwest at high elevations. 

MONDAY: Mostly cloudy. 25-35 cm of snow expected overnight and through the day. Up to 50 cm closer to Squamish. Moderate southwest ridgetop wind trending to extreme at higher elevations. 

Avalanche Summary

On Friday, near Whistler, explosive avalanche control produced mostly small cornice avalanches. One falling cornice caused a slab avalanche on the slope below, 50 cm deep. It was on a northwest aspect in the alpine.

On Wednesday, in the Blackcomb backcountry, two avalanches were reported on north aspects in the alpine: a small, rider triggered windslab, and a large, natural cornice failure that didn't trigger an avalanche on the slope below.

Snowpack Summary

5-15 cm of new snow covers a strong, supportive crust on all aspects into the alpine, and settled, soft snow above 2200 m in shaded alpine terrain.

The rest of the upper snowpack consists of a number of crust/facet/surface hoar interfaces buried in March that seem to have bonded during the recent warm weather. 

The mid and lower snowpack are generally strong and well bonded. 

Terrain and Travel

  • Make observations and assess conditions continually as you travel.
  • Closely monitor how the new snow is bonding to the crust.
  • Use small low consequence slopes to test the bond of the new snow.
  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.

Problems

Storm Slabs

An icon showing Storm Slabs

5-15 cm of new snow may fall overnight into Saturday morning. This new snow may not stick well on the hard crust underneath. Moderate southwest wind could form deeper pockets of more reactive slab in lee features in the alpine.

  • Watch for signs of instability like shooting cracks and recent avalanches.
  • Use extra caution near ridgetops and on convex rolls. 
  • Use small test slopes to see how the storm snow is bonding to the old surface.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Apr 2nd, 2022 4:00PM

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