Avalog Join
Archived

Avalanche Forecast

Jan 26th, 2017–Jan 27th, 2017
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: South Columbia.

Lingering wind slabs may still be reactive to human triggers in steep exposed terrain.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

FRIDAY: Mainly cloudy, Light southwesterly winds, and freezing levels in valley bottoms with alpine temperatures reaching -5 C.SATURDAY: Mainly cloudy with light rain/snow starting in the evening, moderate westerly winds, and freezing levels rising as high as 2000 m.SUNDAY: Mainly Cloudy with light rain/snow, strong southwesterly winds and freezing levels hovering around 2000 m.

Avalanche Summary

Avalanche activity has generally tapered-off with only reports of sluffing in steep terrain with skier-traffic. Lingering wind slabs are expected to be an isolated concern. These should be expected in steep and unsupported or convex wind loaded terrain features. In some areas, recently buried facets and surface hoar may prolong the reactivity these slab avalanches.

Snowpack Summary

20-50 cm of recent snow is settling over the previous mid-January snow surface which includes buried surface hoar in sheltered areas, and/or widespread facets. This slab is particularly touchy where where the buried surface hoar is preserved. Strong southwest winds during the storm have formed wind slabs in leeward terrain features. Isolated subsequent moderate outflow winds may have more recently resulted in reverse wind loading. Another surface hoar/facet persistent weakness that was buried mid-December, can now be found down 70-120 cm and is generally considered dormant. However, we are still receiving occasional reports of sudden results in snowpack tests, suggesting that it has to potential to propagate into a large avalanche if triggered, which is most likely in shallow snowpack areas where the layer is closer to the snow surface.

Avalanche Problems

Wind Slabs

Stubborn old wind slabs may still be reactive to human triggering in steep wind loaded terrain features. In some areas, moderate outflow winds may have caused reverse loading and formed thin new wind slabs.
Be cautious as you transition into wind affected terrain.Avoid areas where the surface snow feels stiff or slabby.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2