Tornado in a Bottle | Science Experiment

Prepare for tornado warnings as homemade twisters turn a soda bottle into tornado alley.

Tornado in a Bottle: Bottled Tornado Science Experiment
Get ready, get set, GO! Prepare for tornado warnings as a homemade twister turns an ordinary soda bottle into your very own tornado alley. (Minus the damage AND the danger, of course!)
How much time does it take to completely empty a 1-liter soda bottle full of water? You’ll find out with this cyclone twist project. This easy-to-create bottled tornado will help kids explore kinetic energy, potential energy and weather. You’ll amaze your dinner guests, your family and your classmates — as well as explore some of the scientific properties of air and water — with this hands-on tornado in water experiment that will make a lasting impression. All you need is a couple easy-to-find items like some 1-liter soda bottles and regular old duct tape. You can also check out our special Tornado Tube (created just for this experiment). Need a lot of soda bottles? Purchase your 1-liter soda bottles here in packs of six or packs of 30.
SICK Science® is a registered trademark of Steve Spangler, Inc. All Rights Reserved

Experiment Videos



Start with two empty, plastic soda bottles. Smaller size bottles work well for smaller hands, but the Twister Tube works on most sizes of plastic soda bottles. Make sure the bottles are the same size.


Fill one bottle 2/3 full with water, attach the twister tube. If you don’t have a Tornado tube, skip ahead to step #4 for instructions.


Attach the second bottle to the other end of the Twister Tube. Make sure that the bottles are screwed on securely so that the water does not leak.


If you do not have a Twister Tube, place a metal washer on top of the bottle with water. Turn the empty bottle upside down and align the openings of the two bottles.  Connect them by wrapping them tightly with duct tape.


Quickly turn the bottle over and set it on a table or desk so it’s standing vertically. A few drops of water might fall into the lower bottle, but not much.  Start moving the Twister Tube in a circle, as if you were stirring something on the stove. At some point, a twister (called a vortex) will form and water will start spiraling into the lower bottle. It looks just like a tornado!

How Does It Work

If you’ve ever watched the water drain from the bathtub, you’ve seen a vortex. A vortex is a type of motion that causes liquids and gases to travel in cool spirals around a center line. The vortex in this experiment is created when gravity pulls the liquid through the bottle’s opening, forming a miniature rotating bottled tornado. Pretty cool, huh?
Swirling the water in a bottle while pouring it out causes the vortex to form; the swirling makes it easier for the air to come into the bottle and allows the water to pour out faster. On the contrary, if you do not swirl the water first and just allow it to flow out on its own, the air and water will then have to essentially take turns passing through the mouth of the bottle (hence the “glug-glug-glug” sound!).

Take It Further

Check out these variations of this tornado in a bottle experiment and mix it up.

Take it Further #1: The Great Pour Challenge
What You Need:
• One (1) empty 1-liter bottle
• Pitcher or bucket
• Water
• Stopwatch

The Great Pour Challenge Instructions:
• Fill the soda bottle to the top with water.
• Here’s the challenge: How long will it take to empty all of the water in the bottle into the pitcher on the table? Record your prediction on a piece of paper.
• Without squeezing the sides of the bottle, time how long it takes to empty all of the water. (You might want to repeat this several times to validate your time.)
• Then, fill the bottle to the top with water just as you did before. This time, however, swirl the water by moving the bottle in a clockwise (or a counter-clockwise) motion while the water pours out. Keep swirling the water until you see the formation of what looks to be a tornado. The water will begin to swirl in the shape of a vortex and flow out of the bottle. Record your time.
• Compare the times. Was one method quicker than the other? If so, why do you think you got these results?

Take it Further #2: A Twist of Color
What You Need:
• Two (2) empty 1-liter bottles
• Tornado Tube OR one washer with duct tape
• 2 ounces of lamp oil
• Water
A Twist of Color Instructions:
Repeat the original instructions of The Great Pour Challenge. This time, however, add 2 ounces of colored lamp oil to the water. (Lamp oil is available at most department stores where oil lamps are sold.) Because oil is less dense than water, the oil will float on the surface of the water. When the oil and water swirl together, the less dense oil travels down the vortex first, creating a “colored” tornado effect.

Take it Further #3: Flying Objects
What You Need:
• Two (2) empty 1-liter bottles
• Tornado Tube OR one washer with duct tape
• An assortment of small objects
• Water
Flying Objects Instructions:
What would happen if you added an assortment of small objects to the bottle with the water? Will the objects that you added spin to the center of the vortex? Or will they spin toward the outside of the vortex? Make your predictions, then follow the original directions; however, add in some small objects to the bottle with the water and see what happens.

Take it Further #4: Styrofoam Bead Timer
What You Need:
• One (1) empty 1-liter bottle
• One (1) 1-liter bottle filled with Styrofoam beads
• Tornado Tube OR one washer with duct tape
• Water
Styrofoam Bead Timer Instructions:
• Carefully open the bottle with the beads.
• Twist on the large connector.
• Twist on a dry 1-liter soda bottle. Turn it upside down to make your own soda bottle timer.
• Now, check and see if this timer is accurate. Is this a good way to measure time? Why or why not? How can we test this?
To take it one step further; you may want to add water and see how this timer compares to the dry timer you have right now!
• Move as many of the beads to one bottle as possible.
• Over the sink, add water to the bottle without the beads. Fill to the brim.
• Add water slowly to the bottle with the beads. You are filling in all of the little spaces in between the beads. As the beads start to push themselves out of the bottle, slow the water and finish filling to the brim.
• This is where it gets tricky; you have to connect the bottles. Carefully attach the Tornado Tube to one bottle then connect the remaining bottle. We suggest doing so over a sink until you get the hang of it.
• Now, check and see if this new water-filled timer is an accurate timer. Is this an accurate way to measure time? Why or why not? How can we test this? Is it more accurate or less accurate than the dry timer? Why do you think you are seeing these results?

Science Fair Connection

Creating a swirling, twirling tornado in water is fun; however, it isn’t a science fair project. Yet! You can create a science fair project by identifying a variable, or something that changes, in this experiment. Let’s take a look at some of the variable options that might work: 

• Compare the time it takes to empty the water from one bottle to another by using the different sizes of Tornado Tubes: one with the large opening compared to the one with the small opening. You may want to also observe and note how the vortex looks during each trial. 

• Try using different sized bottles and determine how that affects the time. 

• Determine the quickest way to transfer the water from one bottle to another. Try it out: shake, twirl, tip, squeeze. What is the fastest method?

These are just a couple of ideas, but you aren’t limited to them! Come up with different ideas of variables to test and give them a try. Remember, you can only change one variable at a time for each test. For example, if you are testing different sized bottles, make sure that all other factors in the test remain the same.

Bottled Tornado Experiments — and More

If you think learning how to make a tornado in a bottle was fun, you’ll think our other Steve Spangler Science experiments for kids are a blast! Steve Spangler Science has science experiments and science fair project ideas for kids that will get them excited about the world they live in. We like to make it BIG and give our experiments that WOW factor that make them memorable and exciting. Learn more about forces and motion, about weather, about air and about energy with our hands-on science experiments for kids.