"Singin' in the Rain" is an episode of The Fresh Beat Band from the second season.
Marina is trying to write a new song, but cannot think of a topic. After a shower passes through, Marina decides to write about the rain. She develops a case of writer's block, so Kiki, Twist, and Shout try to help by re-creating the sound of rain. They also want to figure out if the TV weatherman is listening in on their conversation, a charge he denies. 25