Why does it thunder before it rains?

"Thunder pushes the water mill and the rain overflows the river."

It means that if it rains before it thunders, the wind will be light and the weather will be sultry after it rains, and the rain will be more and more heavy, and the thunder will be heard, which indicates that there will be heavy rain.

On the contrary, if the thunder is neither too slow nor too slow when it rains, it indicates that there will be continuous rain. There is a saying that "after the rain, it will clear up." (golden leaf)

"Thunder and lightning, the storm roared."

In summer, as soon as lightning passes, thunder is heard. Generally, thunderstorm clouds are close to the local area, so the rain comes quickly, and there are often stormy weather, with the momentum of "storm roaring". (golden leaf)