1. By. Amber Summey Science Mr.Shepard

2. Before thunderstorms develop, a change in wind direction and an increase in wind speed with increasing height creates an invisible, horizontal spinning effect in the lower atmosphere. Rising air within the thunderstorm updraft tilts the rotating air from horizontal to vertical..

3. Thunderstorms develop in warm, moist air in advance of eastward- moving cold fronts. These thunderstorms often produce large hail, strong winds, and tornadoes. Tornadoes in the winter and early spring are often associated with strong, frontal systems that form in the Central States and move east. Occasionally, large outbreaks of tornadoes occur with this type of weather pattern. Several states may be affected by numerous severe thunderstorms and tornadoes

4. Tornadoes usually last just a few minutes. The shortest last for only a few seconds Tornadoes are very fast. Here are song speeds. 40-72 mph, Light damage, chimney damage, tree branches broken 73-112 mph, Moderate damage, mobile homes pushed off foundation or flipped over 113-157 mph, Considerable damage, mobile homes demolished, trees uprooted 158-205 mph, Severe damage, roofs and walls torn down, trains overturned, cars thrown around 207-260 mph, Devastating damage, well-constructed walls leveled 261-318 mph, Violent damage, homes lifted off foundation and carried considerable distances, autos thrown as far as 100 meters.

5. Tornadoes can happen at any time of year, they are especially common during the spring and early summer. May and June are the peak months in terms of numbers of tornadoes, but April appears to be the deadliest month.

6. A tornado is a very powerful and damaging windstorm. It can rip apart houses, throw things above the clouds, and do nearly anything destructive. Tornadoes, whether they are a few yards wide or a mile wide, will sweep many miles of land destroying everything in their paths. However, tornadoes are also capable of moving objects without causing any damage whatsoever. This, unfortunately, is rare.

7. Each year, about a thousand tornadoes touch down in the United States, far more than any other country. Nebraska, South Dakota, Oklahoma, Texas and Kansas make up Tornado alley, where tornadoes strike regularly in the spring and early summer. A Tornado can sometimes hop along its path. It can destroy one house and leave the house next door untouched. The United States have an average of 800 tornadoes every year.