Why are storm clouds dark?

Lightning and thunder in sight. The sky turned black from so many dark clouds and here comes storm. It is common knowledge that ordinary clouds are white, while those with heavy storms have a much darker shade of gray. But why are these rain clouds so nearly black?

First, we need to understand how clouds form. The air around us is full of water in its gaseous form, the vapor. When the air near the ground warms, it begins to rise, taking the water vapor with it. Then the air begins to cool as it rises higher in the sky, causing water vapor to condense.

The resulting water droplets and ice crystals merge to form the clouds. Unlike atmospheric particles that scatter more bluish light than other colors (making our sky blue), the small cloud particles equally disperse all light colors, which together form white.

A matter of light

But then how does she look almost black? Rain clouds become gray because of their thickness or height. That is, a cloud becomes thicker and denser because it is more saturated with water droplets and ice crystals. That way, the thicker it gets, the more it scatters light, resulting in less illumination penetrating through it.

As a result, the particles on the underside of the rain cloud don't have much light to disperse from your point of view, so the base looks gray when you look from the earth's surface. This effect becomes even more pronounced the larger the water droplets are, because they become more efficient at absorbing light rather than scattering it.