Song and Dance for Raindrops - Superstition or Science?

Many human communities have a long-standing belief that song and dance can deliver raindrops from the gods.

Nucleation of vapor into liquid droplets
Air may be under-saturated, saturated or super-saturated with water vapor. As 2% of the moisture in the air is always in the liquid state, the 98% of water in vapor form comes into occasional contact with water droplets in the air.
Thermodynamically speaking, both the under-saturated and the saturated conditions are stable, in the sense that the vapor and liquid states continue to coexist indefinitely unless a physical disturbance occurs. 
The super-saturated condition, however, is thermodynamically unstable i.e. the excess vapor in the air is actively wanting to exit from the air and is prone to doing so in liquid water form. In fact, if the super-saturated vapor comes into contact with liquid water droplets and continues to stay in contact for less than a second, this vapor condenses immediately to grow the liquid droplet.


Song and Dance create motion in air
Loud continuous sounds cause air to move (as sound waves cause tiny movements in the air) as does dancing that moves air in chunks the size of our human bodies. The net amount of physical movement of air is, of course, dependent upon the pitch and duration of the sounds we make and the intensity and continuity of our physical movement.
It is thermodynamically proven that on a cool still night, when air is saturated or super-saturated with water vapor, when this air contains water droplets of a critical size, the right intensity and continuity of sound and human body movement can condense water vapor into fog that eventually turns into liquid rain.


This use of sounds to produce rain is also documented in the rain dances in Africa and the use of yelling in the Yunan mountains of China.