Small project done on my freetime, on UE4, combining multiple techniques that I read about on the interweb, at first I wanted to make some water dripping along vertical surfaces with a tweakable treshold and got carried away.
I then added water ripples driven by vertex painting, simple rain and water splash particles and some animated droplets (that might be hard to see on those small gifs).
Ground texture is from the starter content of UE4.