A tornado (often referred to as a twister or, erroneously, a cyclone) is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. Tornadoes come in many shapes and sizes, but are typically in the form of a visiblecondensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds less than 110 miles per hour (177 km/h), are approximately 250 feet (80 m) across, and travel a few miles (several kilometers) before dissipating. The most extreme can attain wind speeds of more than 300 mph (480 km/h), stretch more than two miles (3 km) across, and stay on the ground for dozens of miles (more than 100 km).
According to Head of Data and Information Center for Meteorology, Climatology and Geophysics Agency Region III, Denpasar, Endro Tjahyono, a tornado has few early symptoms such as:
1. The air was hot and sultry
2. In the sky was no growth Cumulus clouds (white clouds clustered in layers)
3. Clouds abruptly changed color from white to black (cumulonimbus clouds)
4. Tree branches and leaves swaying in the wind speed because that feels very cold.
5. If this phenomenon occurs, most likely rain accompanied by strong winds will come.
