A4Tornadoes A4-Tornadoes When Tornadoes Form: • • • • On the Southern Plains, tornado season is from May to early June On the gulf coast, tornadoes form in early Spring In the upper Midwest, most tornadoes form in June or July Tornadoes can happen at any time if the conditions are right. What is a tornado? A small, rotating column of air that has high wind speeds, low central pressure and touches the ground. Difference between Funnel cloud and a Tornado A funnel cloud is a funnel shaped cloud of condensed water droplets, associated with a rotating column of air and extending from the base of a cloud but not reaching the ground. If a funnel cloud touches the ground it is called a tornado. How Does A Tornado Form? A tornado forms when here are two winds, raveling in different directions after a tornado starts to spin, updrafts straighten it, and it becomes visible in the cloud. The updrafts start to spin with the other winds. Funnel Cloud To Tornado (cumulonimbus) After the updrafts straiten the tornado. It makes its way down to the bottom of the tornado, thus forming a funnel cloud. The funnel cloud grows into a tornado when it touches the ground. Tornado Rating Scale Tornadoes are rated on the Fujita scale, which is scaled from F0-F6 with F0 having light damage, and F6 being severe. This system was created by Ted Fujita and Allen Parson. On the right is a detailed chart that shows the accurate winds speeds and possible damage from each levels of the scale (This does not include F6). Where Tornadoes Form 75% if the world's tornadoes happen in the United States. In the U.S. The most common place to find tornadoes is in Tornado Alley. Tornado Alley is in central U.S. Most tornadoes would be found in a flat areas where warm air (from the Gulf of Mexico) meets the cold polar air (fro Canada). This is why the central states of America get many tornadoes. Double Waterspout video!!!