South Columbia

Wind slabs may be reactive to rider triggering. The safest, best riding may be in lower elevation terrain sheltered from the wind.

Moderate - Wind effect is extremely variable

The dominating arctic ridge is slowly breaking down as we transition to a more zonal (westerly) flow. Cloudy with some sunny periods, light-moderate westerly winds and slightly warmer alpine temperatures will persist through the weekend. A more significant change to come early next week.Friday/ Saturday/ Sunday: Mix of sun and cloud with mostly cloudy skies on Saturday. Ridetop winds will be light from the SW-W and alpine temperatures near -12.

On Wednesday, some natural and numerous wind slab avalanches were reported up to size 2 on a variety of aspects. Loose dry sluffing was also noted from southerly slopes. Switching winds will likely promote a reverse loading pattern increasing the likelihood of rider triggered wind slab activity on a variety of aspects on Friday.

Up to 30 cm of low density snow fell earlier this week. Moderate to strong southwest and then northerly winds have shifted these fresh accumulations into reactive wind slabs on leeward slopes. The mid-December facet/surface hoar persistent weakness can be found buried 70-120 cm deep 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, particularly in shallow spots where this layer is closer to the snow surface. The lower snowpack is well bonded and features a thick rain crust near the ground.