Some rain songs

A Hard Rain’s A-Gonna Fall -- Bob Dylan
Here Comes the Rain -- Eurythmics
Fire and Rain -- James Taylor
Purple Rain -- Prince
The Rain Song -- Led Zeppelin
I Can't Stand the Rain -- Ann Peebles
Who'll Stop the Rain? -- Creedence Clearwater Revival
Raindrops Keep Falling on my Head -- B J Thomas
I Wish It Would Rain -- The Temptations
Little Bit of Rain -- Karen Dalton
Listen to the Rhythm (of the falling rain) –- The Cascades

I am sure there are more, but above all else is:
Gene Kelly – Singin’ In the Rain