If there is a cloud of debris coming towards you there is a good chance that there is a tornado in your area, even if a funnel cloud is not visible. Also, if there are strong winds one second, and the next they suddenly die down, and it becomes very calm, then there is a possibility of a tornado forming. Most tornadoes trail behind the storm, so it's not unusual to see sunlight and fairly clear skies before the tornado hits. Most of the time, but not always, large hail occurs when you are threatened by a tornado. RADAR can also detect some tornadoes. A RADAR is a system for detecting the presence, direction, distance and speed of something. RADAR can especially detect the mesocyclones of a tornado. A mesocyclone is a vortex of air that sometimes forms into tornadoes. Due to the curvature of the earth, RADAR is unable to detect some tornadoes. RADAR is also less successful in detecting ground sources because they are short (in terms of time no