Why is it raining in the rainbow and sunny in the evening?

It rains towards the rainbow, and it is sunny in the evening. Reasons:

1. "Rain towards the rainbow": The appearance of morning glow indicates that the water vapor and water droplets in the atmosphere have increased, and the clouds have invaded the local area from the western sky, so it can be predicted that it will turn rainy in the future.

2. "Evening rainbow and clear sky": the appearance of sunset glow indicates that the rain has stopped in the west and the weather has turned fine. Moreover, the bright red and golden red sunset glow often indicates that the atmospheric stability has improved, so it can be predicted that the weather will turn fine in the future.

Formation of chardonnay:

In the morning and evening, around sunrise and sunset, rosy clouds often appear on the horizon. This is due to the fact that before and after sunrise and sunset, sunlight penetrates through the thick atmosphere and is scattered by a large number of air molecules.

when sunlight enters the atmosphere, it will scatter when it meets atmospheric molecules and particles suspended in the atmosphere. These atmospheric molecules and particles themselves do not emit light, but because they scatter sunlight, each atmospheric molecule forms a scattered light source.

according to the Rayleigh scattering law, the light with shorter wavelength such as purple, blue and cyan in the solar spectrum is most easily scattered, while the light with longer wavelength such as red, orange and yellow has strong light transmission ability.

Therefore, the clear sky is always blue, while the light above the horizon is only yellow, orange and red with longer wavelength. After these rays are scattered by air molecules and water vapor and other impurities, the sky there will be colorful.

Extended information:

For thousands of years, working people in our country have summed up rich experiences of "knowing the weather by looking at the clouds" according to the changes in the shape, direction, moving speed, thickness and color of clouds in production practice, and compiled these experiences into proverbs.

1. The morning glow stays indoors, and the evening glow travels thousands of miles:

There are no clouds in the east and clouds in the west in the morning, and the sunlight shines on the clouds and scatters rosy clouds, indicating that there is plenty of water vapor in the air or a rainy system moves in, and the air is generally unstable during the day, so the weather will turn rainy; If there is a sunset glow in the evening, it indicates that the sky in the west has cleared up, and the general convection is weakened at night, and the clouds in the east that form the rosy clouds will move to the east or tend to dissipate, indicating that it will be fine.

2. Cotton clouds, rain is coming:

Cotton clouds refer to flocculent high cumulus clouds. The appearance of such clouds indicates that the middle atmosphere is very unstable. If the water vapor in the air is sufficient and moves upward, it will form cumulonimbus clouds, and there will be thunderstorms.

3. The lock was unlocked in the northwest, and the sun was bright in the Ming Dynasty:

It refers to the rainy day, when the clouds in the northwest opened to reveal a blue sky, which is called "the lock was unlocked in the sky". This shows that the local area is already at the back of the rainy weather system. As the rainy system moves eastward, the local area will stop the rain and the weather will improve.

4. Sunset shoots at the foot, and the rain falls within three days:

It means that the sun shines down from the gap in the clouds, which is called "the sun shoots at the foot", and the sun shoots at night, indicating strong convection and indicating rain.

Baidu Encyclopedia-Xia

Baidu Encyclopedia-Seeing Clouds to Know the Weather