2009-10: The sixth overall pick in the 2009 WHL Bantam Draft when he was selected by Prince Albert in the first round, Winther skated for the UFA Bisons in the Alberta Midget Hockey League. In 28 games he scored 14 goals with 16 assists and had 77 penalty minutes. Winther had no points in the two-game playoff series with Lethbridge.
2010-11: Winther skated in 61 of 72 games for Prince Albert in his first WHL season and played for Canada Pacific at the 2011 U17 World Hockey Challenge. He scored 9 goals with 1 assist and was minus-11 with 18 penalty minutes. The Raiders reached the playoffs despite a sub-.500 record, finishing fourth in the East Division. In four playoff games, Winther was minus-one with no points and 2 penalty minutes. Playing for Canada Pacific, which won a bronze medal at the tournament, Winther had 3 goals with 4 penalty minutes in six games.
2011-12: Winther was the leading goal scorer for a Prince Albert team that had the WHL's worst record and competed for Canada at the 2012 U18 World Junior Championship. In 71 games he scored 32 goals with 24 assists and had 59 penalty minutes. He had a minus-nine plus/minus as the Raiders won just 21 games. Playing for Canada, which defeated Finland in overtime in the WJC bronze medal game, Winther scored 1 goal with 1 assist and was an even plus/minus with 4 penalty minutes. Winther was invited to the NHL Draft Combine and was ranked 21st amongst North American skaters in Central Scouting's final rankings prior to the 2012 NHL Draft.
One of the quicker players off the blocks in the 2012 draft class, Winther’s acceleration is tremendous. He has top speed that puts him in the upper-echelon of his peers as well. His quickness in his feet is matched by the quickness in his release. The puck barely has time to sit fully on his blade before it’s thrown into the back of the net. His wrist shot and ability to load up powerful one-timers is a major strength of a player that really doesn’t appear – physically – to be able to accomplish such feats so effectively. His bloodlines suggest that he might have room to grow, but that’s far from a guarantee. He has decent hockey sense and has a great ability to find openings in the defense. He’s a better fit on the wing than at center given his propensity to shoot. He can play on either special teams unit and is a noted trigger man on the power play. He is still physically immature and can be easily knocked off of the puck. Like many pure goal-scorers, he can go through stretches where he just fades into the background.
Will return to Prince Albert (WHL) in 2012-13.