It can happen not only in the BC but inbounds too. If you have not had Avy training I incourage you to do so.
http://www.google.com/hostednews/ap/article/ALeqM5hC0t6YTXWxsexnFT97Qw5Nu_G1PgD95C30O80
http://military.rightpundits.com/2008/12/27/jackson-hole-avalanche/
http://www.google.com/hostednews/ap/article/ALeqM5hC0t6YTXWxsexnFT97Qw5Nu_G1PgD95C30O80
http://military.rightpundits.com/2008/12/27/jackson-hole-avalanche/