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As of Wednesday, March 28

Another series of weather systems has rolled through our area, although right now it is a beautiful day with the sun shining through broken cloud cover and a fresh blanket of clean white snow over the moist and dirty old snow.

The recent weather pattern has seen systems roll in with very warm temperatures and intense precipitation. This has been followed by a rapid drop in the freezing level and continued light flurries. Before this last system we recorded some very warm temperatures due to daytime warming with the extreme being Lakeside bowl on Blackcomb hitting 18C.

This warming pushed the moist zero degree layer of snow down one metre into the snowpack. Many of the buried weaknesses in the upper layers have been changed by this trend. The following rain and then snow and cooling have changed the main concerns for backcountry travellers.

As temperatures remain cool the surface layers will gain strength, however this stronger layer over the still significant November facet layers may prove a bigger problem in some areas.

Until this recent series of weather events we saw a number of avalanche involvements with isolated areas of slab release on old crusts and surface hoar, with some nasty results. These instabilities have been known to be present since mid-February and should not be discounted.

The avalanche danger rating as of Wednesday, March 28 is CONSIDERABLE. Once again, the weather has been variable lately, with significant fluctuations in freezing level and some strong winds. Cornices are much larger this week than last and may fall when temperatures come up again. This sort of trigger may be enough to pull on the facets. Happy travels, just be aware of the changing conditions.

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