1. Tornadoes

2. Tornadoes
A rapidly whirling, funnel-shaped cloud that reaches down from a storm cloud to touch Earth’s surface.
Usually are on the ground for 15 min or less.
May be only a few hundred meters across
Wind speeds approach 480km/hr (300mph)
If it occurs over a lake or ocean, it is called a water spout.

3. How Tornadoes Form Develop in low, heavy cumulonimbus clouds.
Most likely during spring and early summer, often late in the afternoon.

4. How Tornadoes Form Tornado Alley- located in the great plains.
Cold, dry air moves south from Canada.
Warm, humid air moves north from the Gulf.
Causes a squall line of thunderstorms to form which are severe.
US averages 800 tornadoes a year.

5. Estimated Wind Speed km/h
Fujita Scale
Category
F-Scale
Estimated Wind Speed km/h
Estimated Wind
Speed mph
Effects
Weak F0
km/h
40-72 mph
Minor damage, snaps small branches, breaks some windows F1
km/h
mph
Downs trees, shifts mobile homes off foundations
Strong F2
km/h
mph
Rips roofs off houses, destroys mobile homes, uproots large trees F3
km/h
mph
Partially destroys buildings, lifts cars
Violent F4
km/h
mph
Levels sturdy buildings, tosses cars F5
km/h
mph
Lifts and transports sturdy buildings

6. Tornado Safety
Damage is due to strong winds and flying debris (objects picked up by the tornado)
The low pressure sucks up dust and other objects into the funnel.
Tornadoes can move large objects.
Sheds
Trailers
Cars
Homes

7. Tornado Safety Tornado Watch- possible tornadoes are in your area.
Tornado Warning- a tornado has been spotted on the ground.

8. Tornado Safety
The safest place to be is in the basement of a well built building.
If no basement, move to the middle of the ground floor. (typically a bathroom)
Stay away from windows and doors.
Lie on the floor under a sturdy type of furniture (a large table)

9. Tornado Safety
If in a mobile home or a car, move to a building or lie flat in a ditch.
Underpasses are NOT safe places to seek shelter.
Storm
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