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The whirling tropical cyclones that on occasion have wind speeds reaching 320 kilometers per hour are known as - the most powerful storms on earth. Out at sea they can generate 15-meter waves capable of inflicting destruction hundreds of kilometers from their sou ....

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.... are most noted for their destruction, some parts of the world, especially eastern Asia, rely on them for much of their precipitation. Although numerous tropical storms develop each year, only a few reach hurricane status, which by international agreement requires wind speeds in excess of 119 kilometers per hour and a rotary circulation. Hurricanes average 600 kilometers in diameter, and often extend 12,000 meters above the ocean surface. From the outer edge of the hurricane to the center the barometric pressure has on occasion dropped 60 millibars, from 1010 to 950 millibars. The lowest pressure ever recorded in the United States was 892.31 ....