On Sunday and Monday, several natural wind slab avalanches up to size 2.5 were observed throughout the region, some triggered by cornice falls. These avalanches occurred on most aspects and were mainly in the alpine but a few were at treeline. Slabs were typically 20-30 cm thick. On Tuesday, three separate cornice failures triggered Size 2-2.5 wind slabs on the slope below, one stepped down to a deep persistent weakness near the ground. Skiers also triggered several wind slab avalanches on Monday and Tuesday up to size 1.5. One of the avalanches was remotely triggered from 15 m away. Fresh wind slabs are expected to remain sensitive to human triggering, especially on steep and unsupported (convex) slopes. Winds have recently switched from south to north and wind slabs should be expected on all aspects in exposed terrain.In the far north of the region around Blue River and Valemount, a persistent slab problem still exists. Several large human triggered avalanches were reported early last week.
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