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For residents along Colorado's Front Range, the windstorms known as chinooks can be both a blessing and a curse. The warmth and low humidity that accompany a chinook can bring welcome relief from winter's cold. Temperatures can rise by 30° F or more within a matter of minutes.

But the warm gusts can sometimes become violent. Chinook winds frequently reach hurricane force and can wreak havoc along the foothills. One particularly strong windstorm hit Boulder on January 17, 1982. Wind gusts were clocked in excess of 120 miles per hour. Damage from the storm was assessed at $20 million.

Chinook winds occur when a strong, deep flow of air crosses the Rockies from west to east. Air is forced up by the high peaks of the Continental Divide and then races down the eastern side to the plains below.

The air heats up and dries out as it descends due to the increased atmospheric pressure at lower elevations. This pattern of air flow frequently produces eerie, flying saucer-like clouds called lenticular or lens-shaped clouds by meteorologists. Near sunset, this phenomenon can produce dramatic and awe-inspiring displays.

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Photo credits: © Corbis Images, © NCAR, © NOAA, courtesy NEWS4, Colorado's news channel.