What is the scientific truth of the weather proverb "The sun is in the east and the rain is in the west"?

This is a proverb about the weather, which means it will be sunny if there is a rainbow in the east, and it will rain if there is a rainbow in the west.

Dong hong sun Xi hong Yu

Rainbow is formed by the refraction and reflection of sunlight on water droplets in the air. It appears in the opposite direction to the sun. Because of the movement law of the weather system, it moves from west to east, and a rainbow appears in the west, indicating that the rain area in the west will move and it will rain locally. There is a rainbow in the east, which means the rain area is in the east. If it moves eastward, it will have no impact on the local area, and it will not rain in the future.

As the saying goes, "it's sunny in the east and rainy in the west." In mid-latitude areas, the cloud and rain areas generally move from west to east.

Rainbow is a light image in the atmosphere. It didn't just come out When the atmosphere is very dry, or there are only tiny water droplets in the atmosphere, rainbows will not appear. There will be rainbows only if there are big water drops in the atmosphere. So there is a rainbow in the sky, which means there are big water drops in the atmosphere; At the top of the rainbow, it may have been raining.

The rainbow is in the east, which shows that there is rain in the atmosphere in our east. The atmosphere generally moves regularly from west to east, and the bad weather in the east will only move eastward more and more. If the rainbow is in the west, it means that there is rain in the atmosphere in the west. With the movement of the atmosphere, rain easily falls on us. Therefore, when there is a rainbow in the east, it is not easy to rain locally, while when there is a rainbow in the west, it is likely to rain locally.