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Avalanche Forecast

Dec 4th, 2023–Dec 5th, 2023
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
4: High
The avalanche danger rating at treeline will be high
Below Treeline
4: High
The avalanche danger rating below treeline will be high
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: Glacier.

Might be a good time to linger in your favorite coffee shop, chin-wagging about your early season exploits or future goals, instead of heading into the backcountry.

Travel in avalanche terrain is not recommended until the storm passes through and the snowpack adjusts to the new snow load.

Confidence

High

Avalanche Summary

On Sunday a natural cycle produced results from size 1.5-2.5 in MacDonald Gully's 2, 5, 6, 7, 9, 10, MacD West Shoulder 1 & 2, Avalanche Crests 1, 2, 3, and on the West face of Cheops.

Avalanche activity will increase on Tuesday as the storm continues.

Artillery avalanche control is planned for Tuesday afternoon.

Snowpack Summary

Over the last several days, 30-45cm of new snow covers surface hoar and a thin crust of steep solar aspects. This layer shows 'Sudden' results in snowpack tests and is easily triggered on convex rolls and in steep terrain.

There is ~110cm of snow at tree line, below average for this time of year. Many early-season hazards still exist at or just below the snow surface.

The base of the snowpack consists of weak, sugary facets in most areas.

Weather Summary

A juicy tropical flow will drop ~30cm of snow by Tuesday morning with another 20-25cm during the day and another ~10-15cm by Wednesday morning. Expect winds to be 30-50km/h from the SW and the freezing level to rise up to 2400m early Tuesday morning as a warm air mass moves through.

Terrain and Travel Advice

  • Watch for changing conditions today, storm slabs may become increasingly reactive.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.
  • Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.

Avalanche Problems

Storm Slabs

Surface hoar (10-20mm) has now been buried by ~40cm of snow (~60cm by Tuesday morning). Expect this layer to become reactive as additional snow falls and settles into a storm slab. This layer will be deeper in wind loaded areas.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Very Likely

Expected Size: 1 - 3

Loose Dry

Watch out for sluffing in steep terrain especially above cliffs and around terrain traps. Small avalanches could be enough to trigger the storm slab problem, resulting in a large avalanche.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2