The rain is both calming and a little exciting (all things I like and stim on tend to be that way). Especially that warm rain in the summer, when the drops are huge and fall rarely and you can hear them go "thud...thud....thud" on the leaves.....then all of a sudden it's a shower and the rain is falling in solid sheets. I think it's not only the rain that makes me happy, it's also many other things like watching the leaves or sidewalk shine, hearing the sound of it in the trees, the balmy scents and so on. But the sound of the rain itself definitely is soothing.
But not the fall rain that goes on and on for days, and it's all dreary and gray outside. I grow to loathe the weather at such times. It's probably got to do with my bipolar phases having a seasonal quality - the fall is when things tend to go bad, and I need a lot of sunlight so when it's been cloudy for a long time, I start feeling dull and distressed.
When I listen to music, it's usually like this - I get stuck on a single song or a couple of them, and listen to them until they lose their first fascination. That may take a few days, a few weeks or months. Then I find some other song to get fixed on. Buying an mp3 player was really a good decision; now I don't need to record special cassettes with my favorite songs to listen to, and changing songs or arranging them takes no time at all.