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backcountry advice

As of Wednesday, April 28, 1999 Temperatures cooled drastically during the past several days and have formed a solid melt-freeze crust on all but N. aspects. This crust is overlain by small amounts of new snow, which will likely begin to sluff naturally on aspects hit by the sun. You may be able to find some powder turns on N. aspects. Although the cool temperatures have retarded the isothermal trend within the snow-pack, this trend will once again continue as the temperature climbs, particularly at and below the tree-line and on any aspects exposed to the sun. At this time of year, the key to the snow stability is the presence of a surface crust; whether or not it has formed overnight and how thick it is. Quite frequently it will form with radiant cooling even when temperatures remain above the freezing mark. As this crust starts to deteriorate with warming or with exposure to the sun, the surface layers will begin to lose their strength and any weaknesses deeper within the snow-pack will be more prone to failure. If you are travelling in the backcountry, choose your route so that you are able to avoid any avalanche prone terrain during the heat of the day. Remember that a large cornice fall could trigger an avalanche that would be unlikely to occur with only the weight of a touring party. The backcountry avalanche danger is rated as LOW. This will likely increase with warming and with exposure to the sun.

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