Question

Velocity of sound increases on a cloudy day. Why?

Answer 1

On’ a cloudy day, the amount of water vapor in the atmosphere is much higher
than on a dry day. Thus, density of dry air becomes lesser. Since the speed of sound is inversely proportional to the square root of the density, sound travels faster on a cloudy day than on a dry day.so, velocity of sound increase.

Answer 2

I agree with abhilasha. Another viewpoint is that a cloudy day is more humid. Sound's velocity is inversely proportional to humidity.