Reading Passage The area most One of the nature is the to most feared occurrences in region extending from frequently the Great Plains, the target of this violent windstorm is the When warm, moist air the Rockies to the Mississippi, and from Canada down through Texas. Prior to the formation of meets with cooler, drier air at low levels, tornado often occurs. a the familiar black line suddenly appears. funnel-shaped cloud, the sky is very clear. Then, a As this black area and moist and deep stillness moves in, the fast wind becomes hot encircles the landscape. Because steadily during a tornado, breathing the air pressure drops fau balance themselves in flight. to the ground unable to becomes difficult. In Suddenly a black funnel resembling giant out of the sky, destroying what a whip dips down it touches, and then retreats. Although a tornado usually destroys property rather than lives, an average of 120 people die obvious why yearly as a result of these violent storms. It is the tornado is feared throughout the Great Plains.