text to learn:  Hurricanes and tornadoes
Autor: Gecildo Viana.Produtor do blog..Blog´s  creator | Publicado: 2011-11-19T11:39:00-08:00

Two of the most dangerous storms which afflict America are hurricanes and tornadoes. They are very much feared by anyone who may live in the path of their destruction and cause millions of dollars worth of damage to life and property every year.Hurricanes which usually develop between July and October are similar to cyclones and originate over the waters in the Caribbean Sea. They move upwards hitting the mainland of America somewhere in the Gulf of Mexico or the Atlantic Ocean. Once they hit land they carry tremendous power with driving rain and wind. These winds can attain speeds of over 75 mph. And cover an area of over 500 miles in diameter. At the center of the storm there is an "eye" with relatively fair weather and warm, dry air aloft. The diameter of the eye is usually about 32 kilometers. When the eye passes the relief is only temporary but soon the wind and rain will suddenly reappear from the opposite direction. Every year homes are destroyed by their fury and often lives are lost. Most people who live near the coast are forced to evacuate their homes and to move to safer areas until the storm passes. Floods are caused along the coasts by both the heavy rain and a storm tide that is considerably above normal water level. The high winds, coastal flooding and torrential rains associated with a hurricane cause enormous damage. People living in the wake of a storm are given ample warning to protect their homes. Flashlights or candles are be prepared in case of electric-power failures and plenty of fresh water should be saved as precautions against the pollution of water supplies by flooding.If one should travel inland across the Great Plains and the prairie states of America, one will most likely not encounter a hurricane, but there is another kind of storm in the Midwest which is equally feared. It is called a tornado. Tornadoes are violent low-pressured storms with an intense updraft near their center which is capable of lifting quite heavy objects from the ground. A tornado, therefore, is a dark, funnel-shaped cloud containing violently rotating air. It can pick up trees and cars right into the air and even uplift heavier objects such as homes and railway cars. Like a vacuum cleaner across a rug, it sucks up into the air anything which may lie in its path. These storms occur most often during the summer months and are noticeable by their strong wind and lack of rain. The sky turns black as dust is sucked up into the air. Tornadoes travel normally at around 60 kilometers per hour and the winds can reach 800 kilometers per hours in the most violent storms. Tornadoes are most frequent in the United States east of the Rocky Mountains and especially in the central plains area of the Mississippi basin where about 150 occur each year. Tornadoes may also strike the southern states in winter and have even been known to develop in the northeast. Both hurricanes and tornadoes cause millions of dollars worth of damage each year. Today they can be predicted more easily than in the past, but they cannot be stopped or ignored. When they come they must be endured with the hope that one survives their fury and wrath.