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What Is Wind?

Air may not seem like anything at all; in fact, we look right through it all the time, but during a windstorm, air really makes its presence known. Wind is able to lift roofs off buildings, blow down power lines and trees, and cause highway accidents as gusts push around cars and trucks.

Wind is moving air and is caused by differences in air pressure within our atmosphere. Air under high pressure moves toward areas of low pressure. The greater the difference in pressure, the faster the air flows.

The Fastest Winds

In 1934, on the roof of a little wooden building atop Mount Washington, in New Hampshire, an instrument to measure wind speed, called an anemometer, made history. It recorded a wind speed of 231 miles per hour (mph) during a huge spring storm, the fastest wind gust ever recorded with the instrument!

More recently, sophisticated Doppler radar has been used to measure winds, recording a wind speed of 318 mph in an Oklahoma tornado in 1999. That’s faster than the top speeds of Japanese bullet trains and over three times quicker than the fastest baseball pitch.

Describing Wind

Wind is described with direction and speed. The direction of the wind is expressed as the direction from which the wind is blowing. For example, easterly winds blow from east to west, while westerly winds blow from west to east. Winds have different levels of speed, such as “breeze” and “gale”, depending on how fast they blow. Wind speeds are based on the descriptions of winds in a scale called the Beaufort Scale, which divides wind speeds into 12 different categories, from less than 1 mph to more than 73 mph.

Delve Deeper...

The Beaufort Scale