Tornados

 

What is a tornado?

 

Tornadoes are nature’s most violent storms.

 

  à   à   à

First, heat rises and a storm begins.

  à    à 

Then, when there is air from two directions a spiral begins.

 

Finally, a funnel drops and a tornado is created.

 

 

 

 

 

Where do tornadoes occur?  

The geography of the central part of the United States, known as the Great Plains, is the best place to form tornadoes. More than 500 tornadoes occur in this area every year and it is called "Tornado Alley".

 

 

How much damage can tornadoes do?

You calculate the danger of a tornado on a scale of F0 to F5. F5 is the most dangerous.

Fujita Scale of Tornado IntensityTornado

SCALE

WIND SPEED

POSSIBLE DAMAGE

F0

 64-115 km/h

Light damage: Branches broken off trees; minor roof damage

F1

116-180 km/h

Moderate damage: Trees snapped; mobile home pushed off foundations; roofs damaged

F2

181-252 km/h

Considerable damage: Mobile homes demolished; trees uprooted; strong built homes unroofed

F3

253-331 km/h

Severe damage: Trains overturned; cars lifted off the ground; strong built homes have outside walls blown away

F4

332-418 km/h

Devastating damage: Houses leveled leaving piles of debris; cars thrown 300 yards or more in the air

F5

419-511 km/h

Incredible damage

 

 

 

When do tornadoes occur?
Tornado season is from March through May. Peak times for tornadoes in the northern states are during the summer. A few southern states have a second peak time for tornado outbreaks in the fall. Tornadoes are most likely to occur between 3 p.m. and 9 p.m.

 

South United States à March – May and September- November

North United States à June –September

 

Look at tornado videos on this site

http://www.stormvideo.com/tornado.html