Why is it dark when it rains?

The reason why the sky is gray and white on a rainy day is because the clouds are thicker, and the main manifestation of the thick clouds on sunlight is the reflection, so that the light on a rainy day is weaker than on a sunny day, and the sky is darker than on a sunny day.

Personal analysis is that the clouds obscure the direct sunlight. The sunlight cannot directly hit the ground, resulting in less light and the sky is dark. At the same time, the dynamic range of the human eye is very large, and the pupil aperture range is also very large, and when it rains, the light is dark, and the human pupil is still very small, and it is too late to enlarge.

Even if the brightness drops very little, the human eye feels dark.

When the raindrops are formed, a large number of cloud droplets should be converging, the diameter of the cloud droplets is generally about tens of microns, and the raindrops of heavy rain can reach several millimeters, that is, a hundred times the diameter of the cloud droplets, so the formation of a raindrop needs to consume one million cloud droplets. In this way, the number of cloud droplets in the air is greatly reduced, and the light shines through more, and the sky is bright. In a few moments, raindrops fell from the sky.

Before the rain, the clouds in the sky are thicker, and the number of cloud droplets scatters all the light, so it is darker. After the rain has passed, the clouds have disappeared and the weather has become brighter again.

Before the rain there will be thick clouds, who are the main components of the clouds, as well as all kinds of impurities and floating dust in the air. So it will block out the sun's rays, and the sky will be darkened.

As an elementary school teacher, I ask you this question. When the water vapor in the sky condenses into clouds, the sky will darken when the clouds are high, and the clouds will turn into rain again, so when it rains, it will be dark. When it rains heavily, the cloud cover consumes a lot and the sky brightens.

Clouds not only rely on water, but also rely on dust and other small impurities in the air as the core of raindrops, when it rains, rain clouds in the sky can produce a large number of raindrops, so there is also a lot of dust in it, so it looks gray, sometimes yellow or gray. When it was about to rain, the clouds were so thick that they blocked out the light.

When it rains, the clouds are so thick that you can't find the clouds at all, and the middle and lower parts are black, and in the early morning and at dusk, the sun is so far away that most of the visible light is consumed along the way, leaving only the red light with the longest wavelength.

Because dark clouds obscure the sun, the light is dim.