Who's Flying Now?

After the events that transpired at the Weather Institute, Ash and co. finally arrive at Fortree City. Ash couldn't wait to challenge the Gym Leader, sadly the Gym Leader is helping with the Feather Carnival. Later they meet the Gym Leader, Winona, who scheduled in Ash's request for a Gym Battle, but in the meantime they should have some fun. Meanwhile, Team Rocket has plans of their own. What sinister plot are they up to this time, and why does the carnival bring back such bad memories for James?