What are the different intensities with which the rain falls and what do all indicate?

song-of-the-rain

#1

What are the different intensities with which the rain falls and what do all indicate?
or
When I cry the hills laugh;
Where I humble myself the flowers rejoice;
When I bow, all things are elated.
Cry, humble and bow indicate different intensities with which the rain falls. Explain the three in context.