The word hurricane is from the Spanish word Huracan’ which means “great wind”. You may have heard the words typhoon and cyclone used to describe big storms. Each of these words (hurricane, cyclone, and typhoon) is used to describe a powerful, tropical storm.
If you live in a hurricane-prone area or have lived through a hurricane, like we have located in NC, you already know how powerful hurricanes are and the extent of damage and destruction they cause.
I compiled this hurricane information and hurricane lesson as a way to help our kids understand what they were, especially since we have experience quite a few.
If you’re looking for other weather related activities, check out these weather related activities – make a thermometer, make an anemometer, make a rain gauge, and track rainfall on our rainfall chart.
Table of Contents
What is a Hurricane?Where do hurricanes form?What is the average size of a hurricane and how fast do they move?How Do Hurricanes Form?How Hurricanes FormHow Does the Hurricane Storm Surge Form?Learning About Hurricanes Activity: Creating a Dome of WaterHurricane Lesson Links Hurricane Activities
What is a Hurricane?
Hurricane is used to describe these tropical storms in the North Atlantic Ocean, north Pacific Ocean, and South Pacific Ocean closer to the United States. Typhoon is used to describe these storms in the North Pacific Ocean closer to Japan. Cyclone describes these large storms in the Indian Ocean and in the South Pacific Ocean around Australia.
Where do hurricanes form?
Hurricanes are very large and powerful storms that form where the climate is hot. They form mostly in “the tropics” – areas around 20 º north and 20 º south of the equator, where the water temperature is at least 80º Fahrenheit.
Below is a satellite photograph of Hurricane Katrina that hit the United States in August 2005. While it was not the most powerful hurricane to hit the United States, it is the most costliest to date. The storm looks like a large swirling cloud. When the winds in these tropical storms reach 74 miles per hour, the storm is called a hurricane.
What is the average size of a hurricane and how fast do they move?
A hurricane can be hundreds of miles across. The average size is 300 miles. Use a map to measure 300 miles from your house. How long would it take you to drive 300 miles? Even though hurricanes are extremely powerful, they are slow movers and don’t always move in a straight line. Hurricanes move at about 10 to 20 miles per hour.
To understand how a hurricane forms, let’s do a little activity so your children can see how warm and cold molecules move differently. Hot and cold air is key to the formation of a hurricane.
How Do Hurricanes Form?
How Hurricanes Form
Equipment
Instructions
Notes
What happened in step 6 above? In the video above, you can see what happened when the room temperature food coloring was put into cold water vs. hot water. When the food coloring was in hot water, the water molecules move more quickly and have greater kinetic energy than in cold water. This increased energy causes the water molecules to move apart from one another more rapidly, which increases the space available for the food coloring molecules to move into. As a result, the food coloring molecules are able to spread more quickly through the water in hot water than in cold water.
What is Happening In Steps 9, 10, and 11
The (blue) cold water drops through the hot water to the bottom and the hot water stays near the top. Air does the same thing. Notice how the blue water goes down to the bottom of the warm water and then dissipates. But the cold (red) water, drops down, but then travels back up to the top.
The warm air in a storm moves to the top and the cold air remains at the bottom. The rising of warm air and the movement of cold air into its place is called convection. Storms then form out of the strong, warm air.
You might want to try this convection currents experiment too.
How Hurricanes Form
Once the warm air rises and the cool air rushes in, winds form. Remember, the Earth is always spinning. The rushing winds in these storms begin to move in a spiral as they respond to the spinning of the Earth. But what’s interesting is the direction in which the clouds spiral.
In the photograph above you can see the spiral form of the clouds. Hurricane Andrew was in the Northern Hemisphere where hurricane clouds rotate (or spin) counterclockwise. In the Southern Hemisphere, hurricane clouds rotate clockwise (in the direction a clock moves).
Teacher note: This difference in rotation direction is due to the Coriolis force. This is a great research project for your older students.
Once these rotating winds reach 74 miles per hour, a hurricane is formed. The heavy rains may also have thunder and lightning.
So, hurricanes need 3 ingredients to form:
1. Ocean water that is at least 80º F.
2. Air above the Earth filled with moisture.
3. Winds moving at a high speed in the same direction above the Earth.
How Does the Hurricane Storm Surge Form?
Which of the following do you think causes the most damage during a hurricane and is the deadliest part of a hurricane?
A. Strong winds
B. The storm surge-ocean water levels that can rise 10 to 20 feet higher than normal tide
C. Heavy rains and flooding
The answer is B. The storm surge is the most dangerous part of a hurricane. However, strong winds and flooding are extremely dangerous. The storm surge is not a giant wave. Storm surge is the rapidly rising level of the sea level. Storm surges in hurricanes have raised the sea level as high as 20 feet above normal sea level. That is as high as a 2 story building! It can happen quickly and catch people off guard.
To understand the formation of the storm surge, let’s discuss air pressure. Air is always pressing down on us. It is hard to feel the air between the surface of the Earth and space pressing down on us, but it is! Look at the drawing below. In a hurricane, the warm air is quickly moving up and it takes weight off of whatever is below it. So, instead of a high pressure pressing down on us, there is lower pressure. This area of lower pressure in the hurricane is surrounded by higher pressure on the outside of the hurricane. This caused a dome of water to rise in the hurricane (where the lower pressure is located). This dome of water is the rising sea level—the storm surge.
Learning About Hurricanes Activity: Creating a Dome of Water
Let’s do an easy activity that demonstrates how a dome of water forms.
Creating a Dome of Water
Equipment
Instructions
What is happening.
Before you pulled up on the fishing line, the air pressure across the entire surface of the water and plastic wrap was the same. However, as you pulled up on the fishing wire (to simulate the rising warm air in a hurricane), the pressure on the surface of the water right under the fishing line became lower (the air pressure was pulling up at this point). However, the pressure around the edges of the water remained higher than the pressure right at the center, causing the water under the fishing line to rise up. This area of rising water simulates the storm surge in a hurricane.
Hurricane Lesson Links
Hurricane lesson – ScienceNetLinks.com
Hurricane lesson – WeatherWizKids.com
4th grade hurricane lesson plan – MensaForKids.org
Hurricane lesson plan – DiscoveryEducation.com
Hurricanes As Heat Engines – MyNASAData
Hurricane Frequency And Intensity lesson – MyNASAData
Hurricane educational links – NASA.gov
How Are Hurricanes Formed: a video lesson for kids – TeachHub.com
Hurricane Activities
Printable hurricane tracking charts – NOAA
Make a storm surge model – National Center For Atmospheric Research
Determine the strongest and weakest points of a hurricane
Create-A-Cane online interactive activity – NOAA
The word hurricane is from the Spanish word Huracan’ which means “great wind”. You may have heard the words typhoon and cyclone used to describe big storms. Each of these words (hurricane, cyclone, and typhoon) is used to describe a powerful, tropical storm. If you live in a hurricane-prone area or have lived through a… Read More The Homeschool Scientist