When can be a better moment to code a script about the rain when it is raining outside?

I wrote rain.sh to make it rain inside! The following animated GIF was just a teaser, you can watch a 1-minute clip on YouTube.

https://lh5.googleusercontent.com/-0WJ1vSZcFPs/UdadOwdPEXI/AAAAAAAAE-c/6kuH9hP3cUo/s800/rain.sh.gif

The code was modified from a falling hearts script, I turned hearts into rain drops!