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RADAR over Texas

RADAR is actually an acronym which stands for RAdio Detection And Ranging.

Our scientific understanding of the physical properties and principles of radio waves made RADAR possible. If a series of radio waves are sent out from a transmitter, and the waves don't return, then the air must have been clear for them to travel through. If the radio waves are transmitted, and then bounce back, then some reflective material ("reflector") must have blocked their path.

The travel time for the waves to return to the RADAR receiver can be easily measured. Then, since radio waves travel at a constant speed (186,282 miles per second), the distance to the "reflector" can be calculated and its location determined.

The only challenging part is to determine the nature of the "reflector." Radio waves can be reflected by many objects. Is there a tank or an elephant in the road ahead? Is that a rainshower or an airplane in the air? Fortunately, time and practice have revealed strategies for determining the shape and structure of reflective objects. Different RADAR systems have been developed for detecting different objects.

In particular, meteorologists use Doppler RADAR to locate areas of rain, snow, and other precipitation. Water droplets and ice crystals reflect radio waves. RADAR detects precipitation and creates RADAR images for meteorologists to analyze. They use this information to forecast the weather in your community.

Today, most meteorologists use Next Generation RADAR, or NexRAD, the most advanced nationwide weather RADAR system. Doppler RADAR is part of the NexRAD system. Have you noticed that the reliability of weather forecasts has improved in recent years? Thank NexRAD. Using a powerful computer network, NexRAD measures precipitation, tracks storm formation, and records wind strengths. Your local meteorologist can't offer any guarantees, but, since NexRAD, you can put more faith in the forecast.

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