"If it keeps on rainin', levee's goin' to break," - Memphis Minnie, A Perfect Circle and Led Zeppelin

"Now I, I wish it would rain down, down on me
Yes I wish it would rain, rain down on me now" - Phil Collins

"Raindrops keep fallin' on my head" - B.J. Thomas

"And it's hard to hold a candle
In the cold November rain" - Guns'n'Roses

"No april rain" - 'I Just Called To Say I Love You' - Stevie Wonder

and as mentioned-

"I can't stand the rain 'gainst my window" - Tina Turner, Anne Peebles, Precious Wilson and Eruption

they're all the ones I can think of atm... I know there are more and I know there are some good folk songs with some but I cant think atm... will post when I remember :D