The H2O Winter Classic returns after a three-year hiatus. Day one opens with a surfing competition on the south side of the Huntington Beach Pier; on Sunday, the board riders will reconvene at Mountain High Resort where a slopestyle competition will determine the overall pro, amateur and industry champions. More than 50 athletes are expected to compete, including a dozen invited pro surfers and a like number of invited pro snowboarders. Sunday's competition at Mountain High will conclude with the usual live-music bash (past performers included Blink 182, Pennywise and Jimmy Eat World).