Questions
When does a storm become a hurricane?
What are three ways a hurricane can cause damage?
What should you do if you find out a hurricane is coming to your town?
The Power of Hurricanes
Hurricanes are called different things in different parts of the world. Scientists often use the name tropical cyclone when they talk about hurricanes. A tropical cyclone is a spinning storm that is born over an ocean. If a storm begins over the Atlantic Ocean, it is called a hurricane.
A hurricane is a huge, warm, spinning storm with very fast winds. A hurricane can last for many days, and it can travel a long way. It can also dump huge amounts of rain.
A hurricane starts as a small storm over the ocean. If the water in the ocean is warm enough, the small storm gets bigger and stronger. A storm becomes known as a hurricane when its winds reach 74 miles per hour. The winds of a giant hurricane can be faster than 200 miles per hour.
This photo was taken from space. It shows Hurricane Katrina heading for the coasts of Louisiana, Mississippi, and Alabama.
A hurricane can grow to be about 300 miles wide. A really big one might be 700 miles wide.
In August 2005, Hurricane Katrina came roaring across the Atlantic Ocean and struck the southern coast of the United States. Katrina was about 460 miles (740 kilometers) wide, and its winds reached 215 miles (344 kilometers) per hour. Katrina was a giant hurricane.
Hurricane Emily
Hurricane Floyd
Scientists have a list of names that they give to hurricanes. When they get to the end of the list of names, they go back to the beginning and use the same names again.
But some hurricanes cause so much damage that their names are taken off the list. Hurricane Katrina flooded the city of New Orleans in Louisiana. Katrina also wrecked many other places in Louisiana, Mississippi, and Alabama. Parents may still name their babies Katrina, but no new hurricane will ever have that name. In this picture a U.S. Coast Guardsman searches for survivors in New Orleans in the Katrina aftermath.
There are three ways that hurricanes can cause damage. The first is wind, the second is rain, and the third is a storm surge (a giant wave from the ocean).
The first main cause of damage is very high winds. In 1992, Hurricane Andrew smashed into Florida and Louisiana at 165 miles per hour. At that speed, wind can knock down buildings and send their roofs sailing into the sky. Pictured here is a mobile home park that was completely destroyed.
The wind from Hurricane Andrew pounded this board through the palm tree.
The second main cause of damage is very heavy rain. Hurricanes can deliver tons of rain. Hurricane Floyd dumped 19 inches of rain on the town of Wilmington, North Carolina.
The city was flooded. In some places, there were snakes swimming in the high water that filled the streets. And some of these snakes were poisonous!
The third main cause of damage is the storm surge. A storm surge is a giant wave that is pushed along by a hurricane. The wave can be 30 feet high when it hits land. Hurricane Katrina's storm surge was 25 to 28 feet. This storm surge pushed these boats on land.
In the past, storm surges caused most of the deaths from hurricanes in the United States. But today, scientists have tools to see hurricanes when the storms are still far from land. So now scientists can warn people to get out of the way of a storm surge. This kind of warning saves many lives.