Tornado- rapidly rotating winds that blow around a small area of intense low pressure.
Tornado formation:
1. Flowing air must blow from different directions at different heights.
2. Eventually air moves in a spinning motion.
3. Updraft makes spinning air rise into a column forming a mesocyclone.
Mesocyclone - rising spinning column of air that may be as large as 5 to 10 km across.
4. If mesocyclone shrinks horizontally and stretches vertically, it spins faster.
5. If mesocyclone works it's way down to the ground, it becomes a tornado.
Funnel Cloud - Tornado that has not yet reached the ground.
Family- group of tornadoes spawned by the same thunderstorm.
Tornado Outbreak- when large numbers of tornadoes form along a squall line.
Waterspout- tornado that forms over water
TORNADO LIFE CYCLE:
1. Dust whirl stage- dust and dirt from the earth's surface rotate upward the base of the
cloud.
2. Organizing Stage- visible funnel extends to the ground and the tornado becomes larger.
3. Mature Stage- when it reaches it's greatest size and strength.
4. Shrinking Stage- width gets smaller, begins to lose it's shape and may begin to tilt.
5. Decaying Stage- final stage as it continues to weaken and dissipate.