Avalanche Forecast

Issued: Apr 3rd, 2021 4:00PM

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

Avalanche Canada MBender, Avalanche Canada

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It seems like it is still winter and the snow keeps coming steadily. Expect to see a bit of new snow accumulate through the end of the weekend along with wind blowing from the southwest. Wind slabs are the main concern. 

Summary

Confidence

Moderate - Uncertainty is due to limitations in the field data.

Weather Forecast

Saturday Night: Mostly cloudy. Light to moderate southwest wind. Alpine high temperature near -8.

Sunday: Flurries, accumulation 2-5 cm. Moderate to strong southwest wind. Alpine temperature near -5.

Monday: Continued flurries, accumulation 2-5 cm. Light southwest wind. Alpine high temperature near -5.

Tuesday: Cloudy with flurries. Light and variable wind. Alpine high temperature near -10.

Avalanche Summary

With the highway closed through Thursday, we have no reports of avalanche activity from past several days. There were likely natural storm slab avalanches in the Whitepass area during an intense period of snowfall on Wednesday morning. 

Snowpack Summary

5-15 cm of new snow may accumulate through Sunday and Monday. This will sit on a dump of new snow midweek that brought 30-40 cm to White Pass and 25-30 cm to the hardest hit zones at Haines Pass. The new snow arrived with moderate southwest wind, loading pockets of wind slab into lee terrain features at all elevations. 

There are no deeper concerns in the snowpack around White Pass. The terrain around the Tutshi Lake/Paddy Peak area should be assessed on a slope by slope basis, as lingering snowpack weaknesses may still exist. The Wheaton's shallower snowpack is dominated by hard wind slabs overlying sugary facets and depth hoar. It's an untrustworthy snowpack structure that requires conservative terrain selection and diligent travel habits.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Minimize exposure to sun-exposed slopes when the solar radiation is strong.
  • Extra caution is needed around cornices under the current conditions.

Problems

Wind Slabs

An icon showing Wind Slabs

New snow falling Sunday and Monday combined with primarily will build fresh wind slabs. These may be sitting above older lingering wind slabs from midweek.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 5th, 2021 4:00PM