Book 7, Question 46 · Video
Why Do Flash Floods Happen So Quickly?
A flash flood is a flood that arrives fast, with little warning. Very hard rain can fall faster than the ground and drains can soak it up, so the water has nowhere to go. Flash mea
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What Crafty Clover says in this video
Intro
Hi there, weather detectives! I'm Crafty Clover! Let's discover something amazing. Why do flash floods happen so quickly?
The Big Idea
A flash flood is a flood that arrives fast, with little warning. Very hard rain can fall faster than the ground and drains can soak it up, so the water has nowhere to go. Flash means fast, and the water can rise much faster than you expect.
Hard Rain Falls
Step one: hard rain falls. A strong storm can drop a lot of rain in just a short time, sometimes an inch or more in an hour. The drains and soil cannot keep up.
Water Can't Soak In
Step two: the water cannot soak in. Pavement, roofs, and very dry or burned ground do not soak up water well, so it runs off quickly. That is why cities and burn scars can flood fast.
Rushing Water Gathers
Step three: rushing water gathers. The runoff pours into streets, creeks, and low spots, and the water can rise and rush very quickly. Even shallow, moving water is stronger than it looks.
A Closer Look
Let's take a closer look at a flash flood! Storm clouds drop heavy rain. The hard ground and pavement send it running into the streets. And a low spot fills up fast, so stay away from it.
Quick Facts
Quick facts! A flash flood can build in only minutes, sometimes with no rain right where you are. Just 15 centimeters, about 6 inches, of moving water can knock over an adult. Never walk, play, or ride a bike in sudden street water. If water is rising, tell a grown-up, and move to higher ground away from the water.
Think Like a Scientist
Now, think like a scientist! During or after a gentle rain, watch how water runs off a driveway. With a grown-up, pour a cup of water on soil and then on pavement. See which one soaks in and which one runs away. Ask: why do floods come so fast in cities?
Outro
Flash means fast, so stay away from sudden water. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!