These columns of brown, dust-filled air, which can rise dozens of feet, are not as evil as the name suggests. They are caused by warm air rising on dry, clear days. Winds associated with dust devils can reach up to 60 miles (96.5 kilometers) per hour and cause some damage. There have been reports of dust devils as tall as 5,000 feet (1,500 meters). They are generally not as destructive as tornadoes and usually die out pretty quickly, though some have been known to displace as much as 50 tons (4,500 kilograms) of dust and light debris. One of the biggest dust devils ever recorded was seen in Bonneville Salt Flats in Utah. It was hundreds of feet tall, and it continued on its way for about 40 miles (65 kilometers).