Does your cat or dog run to hide during a thunderstorm? Many dogs do fear the sound of thunder and flashes of lightning. Many children and even some adults are also fearful of storms. If you know anyone who is afraid or nervous during storms, you can help the person get over that fear by observing a thunderstorm with him and teaching him how spring storms are formed, what causes thunder booms, and how lightning works.
Watching Clouds Form
On a spring afternoon watch for thunder clouds beginning to form across the sky. Large white clouds rising high and seeming to pile higher and higher into the air are the beginnings of cumulonimbus clouds. This cloud is the result of warm air rising rapidly as it heats up during the day. The moisture in the air forms a huge bank of cloud.
Watch carefully and you will see that the cloud is always building and changing. In fact, no cloud stays the same shape for more than a few seconds. Observing from the ground, you can watch a cloud change in only a few minutes. The first stage of the thunderstorm formation is Cumulus Congestus clouds beginning to form and build.
Cumulonimbus Clouds
Cumulonimbus Calvus are the clouds with huge white lit-up tops – billowing and fluffy. As the clouds keep building upward a Pileus cloud develops at the peak of the Cumulus Calvus. Think of the Calvus as the calf or child of the cumulonimbus cloud.
This Pileus cloud is like a smooth arch sitting above the clouds. It is flat at its base and since the cumulus clouds are moving so fast they catch up and merge with the Pileus cloud. This shows weathermen that there is most assuredly going to be a big thunderstorm with plenty of wind, rain, thunder, and lightning.
Lightning and Thunder
Lightning is formed when the positive and negative charges in the cloud build up and discharge toward each other. Ice crystals, which are positively charged, rise inside the cloud. Water droplets in clouds are negatively charged and they tend to sink inside. Opposites attract and the charges send a streak of electricity through the clouds and toward the ground. The temperature can exceed 22,000 º F. The air around the lightning bolt superheats, expands, and then quickly contracts. This makes the thunder boom.
Count the seconds between lightning flash and the sound of the rumble to see how far away the storm is. Light travels faster than sound so it takes 5 seconds for the sound to travel 1 mile. Count the seconds, divide by 5, and that will tell you how many miles away the storm is.
Safety and Storms
You would not want to observe a storm like this standing outside with a kite and a piece of metal like Benjamin Franklin did in France in 1752. Franklin could have been killed by a lightning bolt. Watch a storm from a safe place inside a building – never under a tree. A thunderstorm usually drops a huge load of rain, sometimes hail and can come with strong winds even tornadoes. Watching the clouds build is your clue to get to a safe place and prepare to watch the storm. Try taking some pictures of the clouds and from indoors of the lightning strikes.
Using Storm Data
Write down your observations of the storm, including the time it takes from start to finish. Writing about a storm you have watched can lead to a great science report for school and interesting information to share. Use the lightning data and photos for a science fair project or storm safety poster or write about the storm for your school newspaper. Try writing a story or poem about a thunderstorm. Storms are awesome to watch and exciting to read about.
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