Shirley Duke - Tornadoes

TORNADOES

Shirley Duke

A thunderstorm blasts rainwater against the window. Hail falls from the sky and lands with a bounce. A dark twisting shape drops from the gray-black cloud. Time to take coverits a tornado!

A tornado is a column of air that rotates powerfully and drops from a thundercloud to the ground. Not every storm produces tornadoes. Storms vary in the amounts of rain, hail, lightning, and winds they produce. Some spin out tornadoes.

Large tornadoes can have winds as fast as 300 miles (483 kilometers) per hour. They blow trees from the ground, lift cars, and damage buildings and roofs.

Tornadoes occur on the ground and cause damage there. A rotates in the same cone shape. It comes from clouds but it does not touch ground or cause any damage. Still, it can become a tornado if it drops down far enough.

All tornadoes look somewhat different. They can be funnel-shaped, ropy, or wide like a wedge. Wind is clear, but most tornadoes have color. The color depends on the soil and debris they move over and pick up.

Tornadoes may look gray with rain, black, or white. The red dirt of Oklahoma sometimes makes the tornadoes look red. Some are so clear they are hard to see. They can even have more than one funnel.

Tornadoes may be difficult to spot in heavy rain. An F3 tornado with winds up to 200 miles per hour (321.9 kilometers per hour) in 2006 near Wynne, Arkansas, destroyed several houses, mobile homes, and grain silos.

Tornadoes are unpredictable. They can move from any direction. Most move from southwest to northeast. A few move west to east. Their paths can change directions or even turn around.

Short-lived tornadoes may last a few seconds but some can last up to an hour. Most tornadoes last between five and ten minutes before they break up.

A tornado may sound like a rumbling train. It also could make a roaring or whooshing sound. Large tornadoes can sound like a jet overhead.

Fast Fact

Most tornadoes in the Northern Hemisphere rotate counter-clockwise. Tornadoes in the Southern Hemisphere tend to rotate in a clockwise direction.

The United States has about 1,200 tornadoes each year. Records werent kept until 1950 so accurate estimates arent fully known. Canada has about 100 per year.

Tornadoes have occurred in every US state. Some states have more than others. They tend to develop in areas between the latitudes of 30 degrees and 50 degrees. These regions have cold air meeting with warm air. The normal wind speeds are often different. This helps set up rotation patterns in storms.

The largest number of tornadoes occur through the central US, between the Rocky Mountains and the Appalachian Mountains.

States in the central US have a higher than average number of tornadoes. This area is nicknamed Tornado Alley.

Most tornadoes develop during tornado season, although they can form at any time of the year. May through June is a peak time for the Southern Plains region. The Northern Plains and the Midwest have more tornadoes in June and July. Tornadoes most often take place between 4 p.m. and 9 p.m. but can occur at any time.

The best way to avoid a waterspout is to move at a 90 degree angle to its apparent movement. Never move close to investigate a waterspout. Some can be just as dangerous as tornadoes.

Fast Fact

A waterspout is a tornado over water. They are common over southern Florida and the Keys. Marine warnings are issued when waterspouts are seen over waters by the coast. They dont count officially as a tornado unless they reach land. Waterspouts can be dangerous. They turn boats over, cause damage to ships, and injure people.