1. Tornadoes
Tornadoes
We will be reading the book Night of the Twisters. The book is about tornadoes

2. Twisters Funnel cloud Waterspout Tornado Nicknames
Tornadoes
Tornado Nicknames
Twisters
Funnel cloud
Waterspout
You may have heard of some of the nicknames people use for tornadoes. Some very common nicknames are twisters, funnel clouds, or even waterspout. Can you think what do all of these things have in common?

3. Tornadoes
What is a tornado?
A tornado is a violently rotating column of air extending from a thunderstorm to the ground
That brings us to what a tornado is. A tornado is a violently rotating column of air extending from a thunderstorm to the ground. That column of air is what gives the tornado its nicknames.

4. Ingredients needed for a tornado
Tornadoes
Ingredients needed for a tornado
Cold air from the north
Warm air from the Gulf of Mexico
Change in wind direction
Increase in wind speed
Increasing height
Rising air within a thunderstorm
There are some things that are necessary in order for a tornado to form.
A change in wind direction is necessary in order to have a tornado.
As you probably realize, a tornado needs a high degree of wind speed.
Tornadoes need increasing height. They do not just stay at a base level.
Lastly, when you have a thunderstorm, air begins to rise which helps form a tornado.

5. What Exactly Is A Tornado?
Violently rotating column of air (Vortex) extending from a thunderstorm to the ground

6. How Do They Form? Actually, no one knows for sure!
But…We have a pretty good idea…

7. Step 1
Before a t-storm, a change in wind direction and an increase in speed forms an invisible, horizontal spinning effect in the lower atmosphere (at the base of the storm)

8. Step 2
Rising air within the t-storm (updrafts) tilts the rotating air from horizontal to vertical

9. Step 3
Vertical rotation now extends 2-6 miles up into the t-storm. Now a tornado may form and extend from this area of rotation to the ground.

10. Tornado Facts Winds can exceed 300 mph!!!
Around 1,000 occur on average each year in the U.S.
Kill 80, injure 1,500 people each year on average
Can have a path up to a mile wide!!!
Can occur any time of the year, but peak during the spring (March-June)
Occur most frequently in the central U.S. in a region nicknamed “Tornado Alley”

11. is measured by the Fujita Scale.
Tornadoes
Tornado damage
is measured by the Fujita Scale.
Every tornado can be different. Due to this fact, Dr. T. Theodore Fujita came up with a scale which measures the strength of tornadoes.

12. Fujita Scale Category Damage Wind F0 light 40–72 mph
Tornadoes
Fujita Scale
Category Damage Wind
F0 light –72 mph
F1 moderate 73–112 mph
F2 significant –157 mph
F3 severe –206 mph
F4 devastating –260 mph
F5 incredible –318 mph
Here is the Fujita Scale. It has the category of the tornado ranging from F0 to F5. The category of each tornado depends on its wind speed. It has the damage which each type of tornado causes.

13. Where do most tornadoes hit in the United States?
In the United States, the area where the tornadoes
hit the most is called Tornado Alley. The
states which are in the tornado alley are:
Texas
Nebraska
Colorado
Iowa
Illinois
Indiana
Missouri
Arkansas
Looking at all the tornadoes that occur in the United States, there is a particular region in which the majority of the tornadoes occur. This area is called tornado alley. The states which are in tornado alley are Texas, Nebraska, Colorado, Iowa, Illinois, Indiana, Missouri, and Arkansas.
Danger!
Tornadoes!

14. Tornado Watch or Warning?
Tornadoes
Tornado Watch or Warning?
Tornado Watch: A tornado watch is issued when conditions
or the weather is right for a tornado to occur
Do you know the difference between a tornado watch and a tornado warning?
A tornado watch is when the conditions in the atmosphere are right for a tornado to occur.
A tornado warning is when the actual funnel for the tornado has been sited. If this occurs, you should seek shelter immediately. Do you know where you should go when a tornado is occurring?
Tornado Warning: A tornado warning is issued when a tornado
has been seen

15. Where is the safest place to go during a tornado?
Tornadoes
Where is the safest place to go during a tornado?
You might ask yourself where the safest place to be during a tornado is. Well, depending where you are and what resources you have, tells you what your safest place is. If you have a basement, that is the safest place to be. If not, a shower, the center of the room, or an inner hallway. If you are outside, the best place to find is the lowest area like a ditch.

16. Number of Tornadoes in Specific Years
Tornadoes have been increasing throughout the years…gradually, but they have increased. Take a look at the number of tornadoes in 2004 compared to the number of tornadoes in 1979.

17. Songer http://www.pitt.edu/~super1/lecture/lec0761/005.htm

18. A Tornado Develops

48. Summary 1. Name at least one tornado nickname.
Tornadoes
Summary
1. Name at least one tornado nickname.
2. Name one thing needed for a tornado to occur.
3. What is the name of the scale that measures tornadoes?
4. Which state is not in tornado alley: Texas, California,
Nebraska, or Kansas?
See questions.
5. What is it called when conditions are right for
a tornado to occur?
6. Where is the safest place to go during a tornado?