It rain quite often near where I live this few weeks, probably due to the monsoon season. So, I pick a few photos that I took, touch up them in Photoshop and make them rain in AfterEffects. Below are a few screen capture from the final video.
I also model some objects use in this video with Blender3D. For example, the electric pylon and construction crane are 3D models. For me, it is much more easier to model and render in PNG alpha rather than masking a real photo.
I guess I have blend in the 3D models nicely into a 2D background. The last step would be putting in human characters, which is a bit harder for me to do right now.