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Backcountry Advisory

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As of Wednesday, April 16, 2003

Winter refuses to release its grasp on us, and the daily periods of flurries continue. In the alpine terrain, some small slabs have been developing on the lee sides of ridgelines and terrain features. Initially these slabs may be reactive to the weight of a person, but they have been stabilizing rapidly and generally been of little concern by the following day.

The persistent cloud cover combined with occasional glimpses of the sun have been producing "greenhouse effects" that rapidly moisten the surface layers on all aspects. When this occurs, sluffing and snowballing will begin. Each dusting of new snow will provide an easy, available sluffing layer. Once it goes through the initial melt freeze cycle and has an overlying crust, the destabilization process will take longer. Be aware that a seemingly minor clump of snow can eventually entrain a huge mass of "schmoo" and turn into a very destructive force. A small sluff or slab in motion also has the potential to trigger a deeper release.

Avoid travelling under overhanging cornice lines. If your route provides no other options, attempt to pass through the more hazardous terrain during the cooler part of the day. If you feel that there is no hint of a crust left on the surface and you are wallowing down into the moist, isothermal snow, it is probably time to call it a day.

The backcountry avalanche danger is rated as MODERATE. This may increase throughout the day with warming and/or direct sunshine. Obtain the most current information by contacting the W-B information line at 604-938-7676 or the CAA bulletin at avalanche.ca.

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