Radar bounces radio waves off water drops in clouds.
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Weather Radar

Radar is an important part of weather forecasting because it can show rain is located. The radar bounces radio waves off raindrops in clouds. A computer measures how long it takes for the radio waves to reflect back. It then figures out how far away the rain is. The computer also measures how much energy is reflected back. This tells scientists how much rain is in the clouds.

A new kind of radar called Doppler radar can do a lot more. In addition to showing how far away a raindrop is, Doppler radar can also show if that raindrop is moving toward or away from the radar. Scientists know that if the rain is moving, wind must be pushing it. This is how they know where the wind is blowing in the clouds.

Last modified June 11, 2010 by Becca Hatheway.

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