Avalanche Forecast

Issued: Apr 24th, 2022 4:00PM

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

Kate Ryan,

Forecasts are uncertain about the timing and intensity of the incoming system tomorrow.

A rain on snow event could raise the avalanche danger to CONSIDERABLE. Be prepared to adjust your plans.

Summary

Weather Forecast

Little crust recovery is expected overnight tonight. Unsettled weather returns Monday evening with the arrival of a weakening frontal system.

Tonight: Clear periods. Alpine low 0*C. Freezing level (fzl) 1600m. Light SW wind

Mon: Flurries, 10cm. High 2*C, fzl 2300m, moderate SW wind

Tuesday: Flurries, 4cm. High  -1*C, low -6*C, fzl 1900m. Mod W wind

Snowpack Summary

A breakable surface crust can be found up to 2400m. Several crusts exist in the upper snowpack on solar aspects into the alpine.

The April 18th crust, down 5-30 cm, is widespread up to 2200m & higher on solar aspects.

Below treeline, the snowpack has gone through several melt-freeze cycles & is capped by a crust that breaks down with daytime warming

Avalanche Summary

There has been a loose wet cycle to size 2.5 this weekend with the strong solar input. One notable natural size 3 slab avalanche occurred on Friday from a West aspect at treeline on Avalanche Crest (suspected to be windslab on the April 18th crust).

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Loose Wet

An icon showing Loose Wet

With a mild temperature inversion tonight, rain and warm temperatures will increase the hazard later in the day Monday.

  • Avoid terrain traps, such as gullies, where the consequences of a small avalanche could be serious.
  • Use extra caution on slopes if the snow is moist or wet.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Wind Slabs

An icon showing Wind Slabs

Previous SW winds loaded up lee features. These slabs are up to 30 cm deep and sit on top of a crust on all but northerly alpine aspects. These windslabs will gain reactivity if a rain on snow event occurs tomorrow.

  • Use caution on steep lee and cross-loaded slopes.
  • Recent snow may be more sensitive to human triggering on solar aspects where it sits on sun crust

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Cornices

An icon showing Cornices

Cornices are LARGE and may be sensitive to temperature fluctuations, solar radiation, wind loading or just your mere presence nearby. Take necessary precautions if approaching them to access your line and limit your exposure below them.

  • Give cornices a wide berth when traveling on ridges.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Apr 25th, 2022 4:00PM