North Columbia

Recently formed wind slabs are expected to be touchy on Tuesday. Use extra caution in wind exposed terrain and watch for signs of recent wind loading in leeward and cross-loaded terrain features.

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A ridge of high of pressure is forecast to keep the region cold and dry for the next several days. On Tuesday, a mix of sun and cloud is expected with light to moderate northeast wind in the alpine and treeline temperatures around -15C. Wednesday and Thursday are forecast to be sunny with light northeast wind in the alpine and treeline temperatures remaining around -15C.

On Sunday, one natural size 2.5 wind slab avalanche was observed in the Monashees on a northwest aspect at 2200 m elevation. Skiers also triggered four size 1-1.5 wind slabs on northwest through east aspects between 1900 and 2200 m elevation. These wind slabs were typically 20-25 cm thick and one was up to 40 cm thick. On Saturday, skiers triggered three size 1 wind slabs. On Tuesday, recently formed wind slabs are expected to remain reactive to human triggering. Winds have recently switched from south to north and wind slabs should be expected on all aspects.In the far north of the region around Blue River and Valemount, a more persistent slab problem exists. Several large human triggered avalanches were reported early last week. If you are recreating in the Monashees near Blue River or Valemount, use the Cariboos forecast for more representative conditions.

Recent strong shifting winds have formed wind slabs on a variety of aspects in wind exposed terrain. A new sun crust is being reported on steep solar aspects. The mid-January interface is now down 30-60 cm and consists of buried surface hoar in sheltered areas, old wind slabs, and/or widespread faceted old snow. The interface has generally stabilized but isolated weaknesses may still exist where buried surface hoar is preserved. The mid-December surface hoar/facet persistent weakness can now be found down 100-120 cm. This weakness is currently dormant in the south of the region, but may still be sensitive to human-triggers in the northern part of the region near Blue River and Valemount. It is highly recommended to investigate this layer before committing to any large, unsupported features. Read the Cariboo forecast for more information.