TORNADO ( waterspout) , violently rotating funnel-shaped vortex formed in thunderclouds and reaching down to the ground. At ground level a diameter of about 100 meters rotating wind speed ranges from 150 to 500 km / h. In the center of a tornado is an extremely low-pressure area , which draws in dust , forming a dark hand rising to the sky. Around the pipe of rising air is blowing very strong wind , uproot plants and destroying buildings. Tornadoes occur in the depth of the low pressure in the interaction with atmospheric fronts or other weather changes . In continental areas, they are accompanied by extreme heat in late summer , when the ground is the most heated. Tornadoes are most frequent in the central regions of the U.S., but they are both in India and in many other countries. When a tornado passes over the water, it turns into a waterspout . The average life expectancy of a tornado or waterspout - 4 minutes . Stormy storm at the beginning of the rainy season in West Africa, also called a tornado. They
carry with them a squall winds and torrential rains that caused the
collision of warm sea air with dry air flowing in from the north- east
of the Sahara desert.