It rains or snows. The sun shines or clouds cover it. It’s cold or hot. It is weather. Humans cannot control the weather. It is the manifestation of nature that affects all humans. Humans complain about but realize there is very little they can do about. Rain induced floods, blizzards, cold snaps, heat waves- all are weather phenomena that can take life. One of the most powerful weather phenomenon is the tornado.
A tornado is a weather event that exhibits high rotating winds formed as a funnel that extends from a cloud. The disruptive force of tornadoes are experienced each year in middle United States. “Tornado alley” extends from Colorado through Nebraska into Kansas with a reach that spreads from South Dakota into Oklahoma. Although Tornadoes have been observed on all continents except Antarctica, it is this region of the United States that experiences the greatest number of tornadoes. What is it about this region that makes it so ripe for tornado formation?
The first requirement for tornado formation is an area where warm and cold fronts clash. The flat plains of central North America is the ideal battlefield for these opposing fronts. As the warm moist gulf air meets the colder Canadian air masses, the lighter warm air rises quickly pushing the developing cloud higher and higher reaching as high as 6 miles. The moisture carried up cools and drops as rain. Some droplets that rise high enough form ice particles and drops to earth as hail. The horizontal movement causes the vertical winds to swirl inside the cloud. This is the whirlwind that can form an invisible spinning shaft within the cloud. It appears similar to water flowing down a drain. The swirl of particles and moisture forms the funnel shape. As the funnel cloud reaches out from the cloud it sometimes touches ground. The width of the tornado base may be as wide as a mile, although most are just under a 100 yards. Winds inside the tornado cloud may reach higher than 250 miles per hour. Tornadoes move across the ground at 10-20 miles per hour although some have been timed at 70 miles an hour. The force of the winds destroys everything in its path. Tornadoes sometimes seem to bounce as it moves along the ground. Thus as one homes can be destroyed and the next spared. Other times the tornado clings to the ground eating everything in its path. As suddenly as tornadoes appear, they can disappear.
Tornadoes form when temperature contrasted air masses mix. The resulting swirl dips down from the cloud, drawing objects, debris and soil into its swirl. This is what creates the dark, almost black, appearance of a tornado funnel. The force of a tornado is great enough to capture a motel sign in Oklahoma and carry it 30 miles before releasing it on an Arkansas lawn. In an average year, tornadoes take 80 lives and injury 1500 people. Houses, entire blocks and little towns can be leveled.
The study of tornadoes is a major task of meteorologists around the world. The conditions for tornado formation may be observed without a tornado occurring. At present, a tornado watch can be issued that indicates the conditions are present to form a tornado. Radar and visual observation of a funnel cloud moves the watch to a warning. Today’s technology can indicate the path and the approximate time. The system is not perfect. Cases of nighttime tornadoes striking a town without warning still happens. The key is to be alert when conditions for the formation of a tornado are present.
Tornadoes can form in open areas and cause little or no damage. When tornadoes touch ground and destroy a farm house or strikes a city, it becomes a disaster. A natural disaster is when a natural phenomenon, such as a Tornado, causes loss of life or property damage.
