These days the weather patterns have changed in North India. It is raining somewhere. During this time, sometimes small round pieces of ice start falling from the sky along with the water drops, which we call hail. Often a question arises in people’s mind that why does hail fall instead of snow during rain? And when hailstones fall, why are they almost round in shape?

In fact, hail is the result of a completely different meteorological process from normal rain, which is associated with strong thunder clouds, very low temperatures at high altitude and strong winds moving up and down inside the cloud.

How is hail formed?

Hail is not formed only in ordinary clouds, but also in large and high thunder clouds, which are called cumulonimbus clouds. These clouds often bring storms, lightning and heavy rain. When hot air rises quickly, it also takes the water droplets present in the air with it. The temperature at the top is very cold, so these drops freeze and turn into small ice pieces, which are called hail.

How are ice layers formed?

The droplets frozen in the cold part above the cloud form very small snowflakes. The strong wind that rises upwards keeps moving these pieces up and down inside the cloud. Every time these pieces pass through the watery part of the cloud, new water is deposited on them. Then they go up, where this water also turns into ice. In this way, snow accumulates in many layers and gradually the small pieces turn into big round hail.

Why is the shape of hailstones round?

You must have also noticed that the shape of hail is round. In fact, when a piece of ice keeps moving up and down inside the cloud, water accumulates on it from all sides. Due to this it gradually becomes round of equal size. Just like if you hold ice in your hand and press it, it becomes round.

When and why does hail fall on the ground?

Hail falls on the ground when it becomes very heavy and the strong wind cannot keep it up, so it starts falling towards the ground. If the air is hot while coming down, small hailstones melt and become water drops. But larger and solid hailstones do not melt completely and fall on the ground like round pieces of ice.

Why does thunder and lightning occur when hail falls?

In the cloud that forms hail, one part is very cold and the other part is slightly warm. Due to this cold-heat difference and high wind speed, electricity gets accumulated in the cloud. This is the reason why lightning flashes and thunder sounds. That’s why hail often falls with lightning and thunder.