In October 1859, the U.S. military arsenal at Harpers Ferry was the target of an assault by an armed band of abolitionists led by John Brown (1800-59).
A tornado appears as a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground with whirling winds that can reach 300 miles per hour. Damage paths can be in excess of one mile wide and 50 miles long. Some tornadoes are clearly visible, while rain or nearby low-hanging clouds obscure others.t is not uncommon to see clear, sunlit skies behind a tornado. 1  Tornadoes cause an average of 70 fatalities and 1,500 injuries in the U.S. each year. 2  The strongest tornadoes have rotating winds of more than 250 mph.
F5: Incredible tornado (261-318 mph). Incredible damage. About 70 percent of tornadoes are weak and last between one and 10 minutes. About 10 percent of tornadoes are strong and last 20 minutes or more. Only two percent of tornadoes are considered violent. Violent tornadoes cause the most deaths and can last for well over an hour.