Thunder and Lightning

Have you ever seen tall, dark puffy clouds forming on a hot humid afternoon? These clouds bring thunder and lightning. It’s pretty hard to believe that the sky can create electricity and roaring thunder. In my speech i am going to tell you first of what thunder and lightning are, when they should be expected and where they come from.

First off the clouds that bring the thunder and lightning and other foul weather are called cumulonimbus clouds, sometimes nicknamed “thunderheads.” They can actually form any time of day when the temperature falls rapidly higher up in the sky. These tall dark clouds are full of moisture and contain strong up and down air currents. Cumulonimbus clouds may tower more than 50,000 feet, and cover from just a few square miles up to two hundred square miles. Cumulonimbus originates from Latin: Cumulus “accumulated” and nimbus “rain”. These clouds can form alone or in clusters. They create lightning through the heart of the cloud. Cumulonimbus clouds form from cumulus clouds and can further develop into a super cell, a severe thunderstorm with special features. You can expect to see lightning and hear thunder not long after you see a cumulonimbus cloud.

Now To put it simply, lightning is electricity. It forms in the strong up-and-down air currents inside tall dark cumulonimbus clouds as water droplets, hail, and ice crystals collide with one another. Scientists believe that these collisions build up charges of electricity in a cloud. The positive and negative electrical charges in the cloud separate from one another. When the difference in the charges becomes large enough, a flow of electricity moves from the cloud down to the ground or from one part of the cloud to another, or from one cloud to another cloud.

When the positive charges on the ground leap upward to meet the negative charges, the rough downward path of the negative charges suddenly lights up with a brilliant flash of light. Because of this, our eyes fool us into thinking that the lightning bolt shoots down from the cloud, when in fact the lightning travels up from the ground. The whole process takes less than a millionth of a second. Of course lightning comes before thunder. There are words to describe different kinds of lightning. Here are some of them: In-Cloud Lightning: The most common type, it travels between positive and negative charge centres within the thunderstorm. Cloud-to-Ground Lightning: This is lightning that reaches from a thunderstorm cloud to the ground. Cloud-to-Cloud Lightning: A rare event, it is lightning that travels from one cloud to another. Sheet Lightning: This is lightning within a cloud that lights up the cloud like a sheet of light.

Lightning bolts are extremely hot, with temperatures of 30,000 degrees Celsius. That’s hotter than the surface of the sun! When the bolt suddenly heats the air around it to such an extreme, the air instantly expands, sending out a vibration or shock wave we hear as an explosion of sound. This is thunder. If you are near the stroke of lightning you’ll hear thunder as one sharp crack. When lightning is far away, thunder sounds more like a low rumble as the sound waves reflect and echo off hillsides, buildings and trees. Depending on wind direction and temperature, you may hear thunder for up to fifteen or twenty miles. Thunder is only a noise and is nothing to be afraid of. But lightning can be dangerous.

In conclusion Lightning is caused from cumulonimbus clouds and is caused from positive and negative charges in those clouds. Thunder is caused from the vibration or shock wave that lightning causes which means lightning comes before thunder. The heat of a lightning bolt is 30000 degrees Celsius which is hotter than the sun so you wouldn’t want to be caught near one as they could be extremely dangerous. I hope you have learnt something new about thunder and lightning.