Avalanche Forecast

Issued: Mar 13th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Storm Slabs and Loose Wet.

Avalanche Canada jsmith, Avalanche Canada

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15-25 cm new snow and strong south wind have formed reactive storm slabs at all elevations.

Use small low consequence slopes to test the bond of the new snow.

Summary

Confidence

High

Avalanche Summary

Explosive control work on southerly aspects at treeline produced numerous storm slabs to size 2 on Monday.

Snowpack Summary

15-25 cm of new snow, strong south winds, and rising freezing levels have formed reactive storm slabs.

This brings recent snow amounts to 40-50 cm which overlies a variety of surfaces. These include surface hoar (3-5 mm) on shady slopes, wind affected surfaces at treeline and above, and sun crust on sunny aspects.

A layer of surface hoar or sun crust (aspect dependent) can be found down 50-70 cm.

The lower snowpack includes a layer of weak sugary facets near the ground. These facets are slowly gaining strength and no recent avalanches have been reported on this layer. However, we continue to track the layer and watch for any signs of it becoming active.

Weather Summary

Monday Night

Snow; 10-20 cm / 40 km/h west ridgetop wind / Low temperature at treeline around -8 C / Freezing level valley bottom

Tuesday

Mix of sun and cloud / 20 km/h southwest ridgetop wind / High temperature at treeline around -8 C / Freezing level 1200 m

Wednesday

Mix of sun and cloud / 20 km/h west ridgetop wind / High temperature at treeline around -6 C / Freezing level 1300 m

Thursday

Sunny / 10 km/h south ridgetop wind / High temperature at treeline around -4 C / Freezing level 1500 m

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Make conservative terrain choices and avoid overhead hazard.
  • Use small low consequence slopes to test the bond of the new snow.
  • Avoid exposure to slopes that have cornices overhead.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

15-25 cm new snow and strong south wind have formed reactive storm slabs at all elevations.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Loose Wet

An icon showing Loose Wet

Expect natural wet loose avalanches on steep sunny aspects when the sun comes out.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 1.5

Valid until: Mar 14th, 2023 4:00PM