A cyclone is a low-pressure area in the atmosphere in which winds spiral upward. A cyclone can cover and area as large as 1/2 the United States.  All cyclones are characterized by:  1) the atmospheric pressure being the lowest in the middle and  2.) the winds spiral toward the center.  The direction of the spiral is unique because in the Northern Hemisphere the winds blow counter-clockwise  and  in the Southern Hemisphere the winds blow clockwise.
        Cyclones are also characterized as tornadoes, hurricanes and typhoons.  A tornado is a smaller kind of cyclone it is usually 300 yards (274 centimeters). When a cyclone forms over tropical waters in the North Atlantic or eastern North Pacific oceans and has winds of 74 miles (119 kilometers) per hour or more it is called a Hurricane.  If the cyclone forms in the western Pacific with winds of 74 miles (119 kilometers) per hour or more it is called a Typhoon.  All of these storms can be accompanied by high winds, terrible rains, severe thunder, and lightining.
        When a cyclone occurs storms are usually with it because the falling atmospheric pressure is an indication that bad weather is approaching.  However, there are times that a cyclone forms in dry air and therefore there are no clouds to bring moisture.
        The two types of cyclones are cold-core and warm-core.  A warm-core cyclone is warmer at the center than around the edges.  Warm-core cyclones are very shallow and become weaker towards the upper atmosphere.  These cyclones form over warm lands.  A cold-core cyclone