Sea To Sky

Natural avalanche cycle expected on Sunday. Travel in avalanche terrain is not recommended.

High -

SUNDAY: 30-50 cm of new snow(rain below roughly 1500m) / Strong southwesterly ridgetop winds / Freezing level rapidly rising to around 1800m.SUNDAY NIGHT: 15-25 cm of new snow(rain below roughly 1500m)  / Strong southwesterly ridgetop winds / Freezing level around 1800m.MONDAY: 15-25 cm of new snow(rain below roughly 1500m)  / Strong to extreme southwesterly ridgetop winds / Freezing level around 1800m.TUESDAY: 5-10 cm of new snow / Moderate southwesterly ridgetop winds / Freezing level dropping to around 800m.

Throughout this region there has been evidence of a natural avalanche cycle up to size 3 that occurred within the storm snow on Wednesday. More notable are the numerous explosive triggered, very large avalanches up to size 3.5 that where reported near Whistler on Thursday. Two additional explosive triggered 3.5's were reported Friday. These avalanches started in the storm snow and then stepped down to the early January and even the mid-December crusts which resulted in very large avalanches running full path. They occurred on northwesterly aspects below rocky ridgetops between 1950-2200 m. Although these layers are over 200 cm beneath the snow surface, a large trigger such as a falling cornice or a smaller human triggered avalanche could very likely "step-down" to these layers resulting in large and destructive avalanches.

15-20 cm of new snow on Saturday morning brings recent storm totals to around 80-100 cm which continues to be redistributed by strong southeasterly winds which are creating dense storm slabs lurking in lee and cross-loaded features. Impressive cornice growth has also been observed on the lee side of ridgetops. 200-250 cm below the surface you'll find a crust that was buried early January and is present at all elevations. Below this there is another crust which was buried in mid-December. Recent explosive control work has triggered storm slab avalanches that have then "stepped-down" to both of these crusts, resulting in very large avalanches running full path. Although these layers are over 200 cm beneath the snow surface, a large trigger such as a falling cornice or a smaller human triggered avalanche could very likely "step-down" to these layers resulting in very large and destructive avalanches.