6-8 why and where

7/29/2019 6-8 Why and Where

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LESSON PLAN 1

Why and Where DoTornadoes Form?The word tornado comes from the Spanish wordtronada, which

means thunderstorm. Although a tornado is not a thunderstorm, it

would not exist without strong thunderstorms. A tornado is a violently

rotating column of air extending from a thunderstorm to the ground.

The most violent tornadoes have rotating winds of 250 miles (402 kilo-

meters) per hour or more.

Key Terms and Concepts

anvil cloud

condense

convectioncumulonimbus cloud

cumulus cloud

debris cloud

downdraft

Purposes

To impart to students an understanding of how tornadoes form

and the weather cycle of tornadoes

To have the students identify tornado-prone locales in the United

States and describe the unique interactions of geography and

climate that result in tornadic storms

Objectives

The students will

Watch a demonstration of tornado formation, hypothesize about

its formation and describe their observations.

Research tornado formation usingHow Tornadoes Form.

Write about the experiences of a water drop on a journey from the

Gulf of Mexico to Tornado Alley.

Research to collect information on tornadoes, downbursts and

microbursts; use the information to present an illustrated report.(Linking Across the Curriculum)

Create a glossary to support a study of the connections among

tornadoes, geography and climate.

Tornadoes68

Tornado Science

1Masters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?

Copyright 2007 The American National Red Cross

Visit the American Red Cross Web site

at www.redcross.org/disaster/masters

front

funnel cloud

hailmesocyclone

occluded front

supercell

thunderhead

thunderstorm

tornado

updraftvertical wind shear

vortex

wind shear


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LESSON PLAN 1

Why and Where DoTornadoes Form?

Research and use maps to illustrate answers to questions about the

relationships among tornadoes, geography and climate on A

Cartographers Guide to Tornadoes.

Use information from their glossary and research to write reports on

tornadoes, geography and climate.

Share and exchange information with their families about tornadoes;

research the authenticity and science associated with new facts;

compile a book of tornado facts and fiction. (Home Connection)

Research to find and graph statistics on tornado activity and tornadodeaths by state using the Internet andTornado Mapping; determine

whether improved forecasting technology has improved tornado death

statistics. (Linking Across the Curriculum)

Activities

Youre the Meteorologist

Tornado Alley






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LESSON PLAN 1


3

Materials

Vacuum cleaner

Electric fan

Block of dry ice

How Tornadoes Form, 1 copy

per student

Chalkboard and chalk or

poster paper and markers

Youre the Meteorologist

SET UP 40 minutes CONDUCT two 40-minute classes

Science: Earth Science; Language Arts: Research and Writing

Help the students understand the weather science of tornadoes through the

following demonstration, research and presentations.

1. Gather materials and then set up the tornado demonstration.

Place the electric fan about 20 feet (6 meters) from the block of

dry ice. Turn the fan on, blowing toward the ice. Hold the

vacuum cleaner so that its suction end is about 6 inches (15

centimeters) above the block of ice.

A tiny, short-lived tornado forms, violent enough to pick up

pieces of the frost from the dry ice and blow it from the vortex.

2. Have the students describe their observations and hypothesize answers

to the following questions:

Why does the tornado form? (Wind generated by the fan creates

a shear in the general airflow of the room.)

Why was it able to pick up pieces of dry ice frost? (The airflow

from the fan that passes over the block of ice is then caught in

the suction, intensifying the vortex motion, stretching it up

toward the vacuum.)

3. Challenge the class to use dictionaries or glossaries to definethe words they may not know in How Tornadoes Form.

cumulonimbus cloud

debris cloud

front

funnel cloud

Work with the class as a whole to write the definitions on the chalk-

board or a large piece of poster paper.

4. DistributeHow Tornadoes Form to students and give them time to readthe information. When they have finished, discuss the steps nature takes

to generate a tornado. Ask the students to imagine themselves as drops

of water that eventually become part of a tornado. What events and

what changes would the drops experience?

Masters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?Copyright 2007 The American National Red Cross



TEACHING NOTE Use protective gloves and tongs when handling dry ice.

mesocyclone

supercell

thunderhead

tornado

updraft

wind shear


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Tornadoes68

LESSON PLAN 1


Wrap-Up

Challenge students to write about the journey of a water drop

that begins as water vapor in a warm front over the Gulf of

Mexico and ends in a tornado in Kansas. The account can be written as a

diary, a letter to friends who remained in the Gulf or a cartoon strip.

Instruct the students to illustrate the journey of their water drop and include

the following scientific information on the formation of tornadoes:

The collision of warm and cold fronts: What happens to the water

drop when the fronts collide? The formation of cumulus and eventually cumulonimbus clouds:

How do the cumulus clouds become cumulonimbus clouds or thunder-

heads? Would the drops freeze? Would they be bounced around in the

developing storm?

The formation of a mesocyclone: What happens when the drops

experience wind shear? What sounds might the drops hear? How

might the perspective of the water drops change?

The formation of a funnel cloud: How do the drops end up in the

funnel cloud? What will they encounter in the cloud of water and

dust?

The formation of the tornado: What is the tornados strength? Whatis it like to be part of a huge vacuum as it touches down to the earth?

How big is the tornado that the drops have joined? What do the drops

see happening on the earth as the tornado moves along its path?

Students must use as much scientific detail as possible in their

journeys. However, remind them that the best stories weave the

science into the narrative creatively to make the fictional journey

more interesting and more real.

When students have completed their writing, share the stories in a class

presentation or as a bulletin-board display.

Linking Across the Curriculum

Science: Earth Science and Physical Science

Severe storms, including tornadoes, downbursts and microbursts

(stronger downbursts), have all occurred in the Lansing, Michigan, area

between 1997 and 2001.

1. Divide the class into three groups. Assign one specific type of weather

event from the Web site Tornadoes and Severe Weather

(http://www.msu.edu/~fujita/tornado ) to each group to read.

2. Then, have them use the resources below to search online for picturesand graphic representations of as many of these types of storm as

possible.

3. Using their information, have them make a brief presentation for a

meteorological conference, including a lecture and accompanying

pictures and graphics.






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LESSON PLAN 1


5

Resources

Microbursts and Downbursts

Microburst Animation

(http://www-frd.fsl.noaa.gov/mab/microburst/vu_micro.html)

All About Derechos

(http://www.usatoday.com/weather/wtsm1.htm )

Deadly Winds from Thunderstorms

(http://www.usatoday.com/weather/tg/wmcrbrst/wmcrbrst.htm )

National Weather Service: Microbursts (Three slides:Microbursts, Wet Microburst and Dry Microburst)

(http://www.wrh.noaa.gov/mso/train/img28.html)

National Weather Service Glossary for Storm Spotters

(http://www.srh.noaa.gov/oun/severewx/glossary3.php )

University of Illinois: Microbursts

(http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/svr/comp/out/mi

cro/home.rxml)

National Weather Service Report: Brief Description of

Microbursts and Downbursts

(http://www.srh.noaa.gov/jax/events/windshear.html)

Tornadoes

The Weather Channel: Special ReportsTornado!

(http://www.weather.com/newscenter/specialreports/tornado/

index.html)

Tornado Project Online (http://www.tornadoproject.com/)

The University of Illinois, WW2010: Tornadoes

(http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/svr/torn/

home.rxml)

National Oceanic and Atmospheric Administration Photo

Library: Tornadoes

(http://www.photolib.noaa.gov/nssl/tornado1.html) Horsburgh.com: Tornado Alley

(http://www.horsburgh.com/h_tornado.html)

Think Quest: Thunderstorms and Tornadoes

(http://library.thinkquest.org/C0112425/stu_thundertornado.htm )





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LESSON PLAN 1


Materials

Computer access

Books on weather and geog-

raphy of the United States

Dictionaries and weather glos-

saries

A Cartographers Guide to

Tornadoes, 1 copy per team

Tornado Mapping, 1 copy per

student (Linking Across the

Curriculum)

Chalkboard and chalk or

poster board and markers

Tornado Alley

SET UP 1520 minutes CONDUCT two 40-minute classes

Science: Earth Science; Social Studies: Geography and Mapping

1. Divide the class into three teams, provide them with diction-

aries and weather glossaries and have students define one-

third of terms below. On a large poster board or chalkboard,

work with the class to compile the teams definitions into a

complete glossary. Briefly, work with a globe or world map to make sure

students can locate the natural features and lines of latitude and longi-

tude listed in their glossary.

anticyclone

Appalachian Mountains

climate

cold front

continental

cyclone

downslope

2. DistributeA Cartographers Guide to Tornadoes to each team.

Give them time to answer the questions on the activity sheet,

using the books on weather and geography and the Internet.

Answers toA Cartographers Guide to Tornadoes

1. Weather in the United States is influenced by four air masses. What are

they?

Tropical: These air masses form over the tropic latitudes. They are

warm, humid and have low air pressure.Polar: These air masses form north of the 50

o

line of latitude. They

are cold and have high pressure.

Maritime: These air masses form over the oceans, so they are

humid.

Continental: These air masses form over land, so they tend to be

drier than maritime air masses.

2. What forces move these air masses around? What direction will they

take as they move toward and into the United States?

The jet stream is a prevailing, upper-level, westerly wind. Itmoves from west to east in a sinuous line that changes with the

strength of the cold fronts moving south.

A cyclone is an area of low pressure around which the winds

flow counterclockwise in the Northern Hemisphere. A devel-

oping cyclone is typically formed by a warm front pushing north-

ward and a cold front pulling southward.





Great Plains of the

United States

jet stream

latitude

longitude

maritime

polar latitudes

occluded front

Rocky Mountains

tropical latitudes

upslope

warm front


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LESSON PLAN 1


7

Air masses move south from the arctic land mass, southwest

from the northern Pacific, southeast from the northern Atlantic,

north and then northeast from the Tropics.

3. How might the landforms of the United States affect the air masses

moving through the area?

When air is confronted by a mountain, it is lifted up and over the

mountain; as it rises, it cools. If it reaches its dew point, it will

condense and form a cloud and probably precipitation. Usually,the wind releases its moisture on the west side of the mountains,

and as it flows down onto the plains, the drier air begins to

warm.

There is no barrier to the movement of air masses between the

Gulf of Mexico and the states of the Great Plains.

4. What is a cold front and what is a warm front? What happens when

the two air masses collide?

A cold front is an air mass characterized by cold, dense air. Cold

fronts have winds that move in a clockwise direction. They are

sometimes called anticyclones. A warm front is an air mass of light, warm air. Warm fronts have

winds that move counterclockwise and are called cyclones.

When a cold front collides with a warm front, it slides under the

warm front and pushes the lighter, warmer air upward. The warm

air cools down, condenses and forms cumulus clouds. If there is

enough warm air, as in the summer, it may form cumulonimbus

clouds and even tornadoes.

5. Based on information about the formation of cumulonimbus clouds,

why does an occluded front create excellent conditions for the forma-

tion of severe thunderstorms and eventually tornadoes?

An occluded front occurs when a warm air mass is trapped

between two cold air masses. The warm air is pushed upward when

the two cold air masses meet in a kind of squeeze action. The

warm air mass is completely cut off from the ground by the colder

air below. The warm air has nowhere to go but up, resulting in thecreation of high, strong cumulus clouds. As it cools, it will fall and

then be pushed up again, adding energy to the updraft.

6. Collisions between cold, dry air masses and warm, moist air masses

take place in the Great Plains. This part of the United States is some-

times called Tornado Alley. Compare an alley in your town to Tornado

Alley. How are they similar?




TEACHING NOTE Information about the formation of cumulonimbus clouds and

their relationship to the formation of tornadoes is found in the preceding activity

Youre the Meteorologist.


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LESSON PLAN 1


Possible answer: An alley is a narrow street with walls on both

sides. Tornado Alley is a geographic corridor in the United States,

which stretches north from Texas to Nebraska and Iowa. In the case

of Tornado Alley, the walls on either side of the alley are the two

mountain ranges, the Rocky Mountains and the Appalachian

Mountains.

7. Tornado season tends to move north with the sun. That is, tornado

season starts earlier in the southern part of Tornado Alley than in itsnorthern regions. Why is spring the most active time for tornadoes?

Use the same reasoning to explain why the southeastern states some-

times have a mini-tornado season in the fall.

Spring and summer comprise the prime thunderstorm season; so it

is also prime tornado season in the Great Plains. The reason is that

during these seasons, the air temperature decreases dramatically as

the air rises (called the temperature gradient). Moreover, as the

earth rotates around the sun, the surface warms, releasing energy

(heat) and water vapor.

Severe thunderstorms need large infusions of energy to build into

supercells and tornadoes. The warmer the surface, the more energy

is available. Energy and water vapor are released from the warmsurface and rise in buoyant plumes which, when combined and

organized, form a thunderstorm cell. Therefore, spring and summer

have the greatest possibility for the development of thunderstorms.

3. Ask students to share their findings and then work with them to correctany misconceptions and complete any answers that need more detail.

Remind them they will need correct and thorough information for the

Wrap-Up that follows.

Wrap-Up

Divide the following writing assignments among the

three teams of student writers:

Print Journalism: Background on Geography and Tornadoes for a

local newspaper

Broadcast Journalism: Feature piece on Tornado Alley

Illustrated glossary in which all the vocabulary words listed atthe beginning of the activity are defined, illustrated and

combined in two or three brief paragraphs on Tornado Alley.

Students will work together to create the text and images for their writing

assignment. They must incorporate the facts about geography, climate and

tornadoes from the class research and discussion. Have writers share their

work in a class presentation.





TEACHING NOTE In the discussion that follows, make sure each team appoints a

member to act as secretary. As the teams compare their findings, the secretaries

must update any information or data missing from their teams notes.


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LESSON PLAN 1


9

Home Connection

Have students share their information with their families and

then ask family members to share any facts or concepts they

know, or think they know, regarding tornadoes. Ask students to bring the

new facts back to school to research for authenticity and science. As a

class, compile a booklet of fact and fiction on tornadoes based on what the

students have learned in their research.

Linking Across the CurriculumMathematics: Charts and Graphs

Have the students research the National Weather Services

Weather Storm Prediction Center (http://www.spc.noaa.gov/climo/torn/

monthlytornstats.html) and examine Tornado Mappingto find statistics on

tornado activity and tornado deaths by state. What are the state averages?

They will use this information to develop a graph showing tornado activity

and tornado deaths by state. Challenge the students to calculate whether or

not the percentage of deaths caused by tornadoes is decreasing now that

forecasting technology has improved. Students may also research living

conditions that contribute significantly to loss of life during tornadoes,

specifically, growing numbers of people living in manufactured homes.





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How Tornadoes FormPage 1 of 3

Name ________________________________________________________________________

HOW TORNADOES FORMMasters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?

Copyright 2007 The American National Red Cros



Atornado is a violently rotating column of air, extending from a thunderstorm to theground. The most violent tornadoes have rotating winds of 250 miles (402 kilometers)per hour or more.

Tornadoes form in the following sequence:

FrontsIn the atmosphere, cool air pushes against warm air. The place where the two massesof air meet is called afront. A front can stretch over 100 miles (161 kilometers).

As the cool air presses forward, it slides underneath the warm air. The warm air ispushed upward and water droplets form. Fast-growing clouds take shape. These clouds

are called thunderheads. A line of thunderheads 100 miles (161 kilometers) or more inlength may grow along a front.

ThunderheadsThunderheads, orcumulonimbus (kyu-mya-lo-NIM-buhs) clouds, are the giant cloudsthat produce storms with lightning and thunder. When you see a thunderhead, you arelooking at a place in the sky where warm, moist air is rising quickly through cool air.This can happen along and ahead of fronts as well as on hot, sunny days.

When the sun heats the ground, the air near it grows warm, too. The warm air rises, butit sometimes becomes trapped by a layer of cooler air above it. As the day continues,the sun keeps shining and more heated air pushes its way skyward. Finally, it breaks

through. The warm air blasts high into the sky, like water shooting up from a fountain,and a thunderhead grows.

The thunderheads most likely to cause tornadoes are those that form along and aheadof fronts. This is because strong winds often blow high above fronts. The power ofthese winds, along with slower winds closer to the ground, can make the rising air in athunderhead start rotating. This difference in wind direction and speed is calledwindshear.At first the rotating winds spin around a horizontal axis parallel to the ground.However, as the warm air continues to rise, the updraft becomes strong enough to liftthe rotating air into a vertical spin, roughly perpendicular to the ground.

Asupercell is a thunderstorm with a persistent rotating updraft. Supercells are rare,but they are responsible for a remarkably high percentage of severe weather events,especially tornadoes, extremely large hail and damaging straight-line winds. Supercells


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frequently travel to the right of the main environmental winds; that is, they are rightmovers.

MesocyclonesIf the rising air in a thunderhead begins to rotate, the column of spinning winds is called amesocyclone (mez-uh-SY-klon). As a mesocyclone rotates, it stretches toward warm airnear the ground. The lower part of the mesocyclone narrows. The narrower it becomes,the faster it spins.

The mesocyclone acts like a giant vacuum-cleaner hose. Warm air is drawn in through thelower end of the mesocyclone and pulled upward through the thunderhead. The air swirlshigher and higher. The spinning air may soar all the way to the top of a thunderhead, 10

miles (16 kilometers) above the ground.

Some mesocyclones spin like this for a few minutes and then just disappear. In others,however, a smaller column of faster-spinning air forms inside the bottom of the meso-cyclone. This column is usually less than a half-mile (800 meters) wide. As it spins, itreaches toward the ground.

Funnel CloudsWhen the column of tightly spinning winds dips down from the mesocyclone, it draws inwarm, moist air. The air cools as it is pulled up into the column. Tiny droplets of waterform and a whirling cloud appears. This cloud is called afunnel cloud.

Funnel clouds are named for their shape. They are often shaped like funnelstubes thatare wide at the top and narrow at the bottom. Some funnel clouds hang straight downfrom the storm cloud. Others stretch sideways through the sky. A funnel cloud may dipdown and then retract into the mesocyclone. Or, it may touch the ground. If it does, thefunnel cloud is called atornado.

Sometimes when a tornado is forming, no funnel cloud can be seen. The air near theground is so dry that, when it is sucked into the whirling column, no water droplets form.Then the fast-spinning air stays invisible until it becomes a tornado, stirring up dust andsoil into a spinning debris cloud.

TornadoesIf you see a funnel cloud dip down from a thunderhead, it is usually a sign that a tornadois on its way. But not all tornadoes look like funnels. They can be shaped more like jars


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with the same width from top to bottom. Or, they may have more than one funnel. Largetornadoes may have several narrow, twisting funnels circling around.

Some of the largest, most dangerous tornadoes do not look like funnels at all. These torna-does appear to be big clouds moving along the ground. Tornadoes also change shape withtime. Many funnels become thin, like pieces of rope, as they lose power. They look likegiant elephant trunks snaking through the sky. The winds of a tornado can be so strongthat they can blow large objects, such as parts of buildings, trees and cars, for miles.

Tornado TypesThere are three types of tornadoes: weak, strong and violent. On the Enhanced FukitaScale (EF Scale), these range in intensity from EF0 to EF5.

Weak Tornadoes (EF0, EF1)If the winds of a tornado spin at 110 miles (177 kilometers) per hour or less, scientistsconsider the tornado weak. Weak tornadoes usually leave behind a path of damage lessthan 3 miles (5 kilometers) long and 50 yards (46 meters) wide. Weak tornadoes are themost common of the three tornado types.

Strong Tornadoes (EF2, EF3)Strong tornadoes have winds ranging from 111 to 165 miles (178 to 266 kilometers) perhour. These tornadoes average a path about 9 miles (14 kilometers) long and 200 yards(183 meters) wide.

Violent Tornadoes (EF4, EF5)Violent tornadoes are the least common type of tornado. Only 1 in 50 tornadoes in theUnited States is classified as violent. These tornadoes have winds ranging from 166 tomore than 200 miles (267 to 322 kilometers) per hour and may last several hours. A typicalviolent tornado leaves a path of destruction about 26 miles (42 kilometers) long and 425yards (389 meters) wide. A few violent tornadoes have left paths that were more than 100miles (161 kilometers) long and 1 mile (1.6 kilometers) wide.


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A Cartographers Guide toTornadoesPage 1 of 3

Name ________________________________________________________________________

A CARTOGRAPHERS GUIDE TO TORNADOESMasters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?




Directions: Research to find the answers to the following questions. You will need to

investigate both books and Internet resources to find the answers.

1. Weather in the United States is influenced by four air masses. What are they? On the

map on the third page, show where these air masses can be found.

2. What forces move these air masses around?

Hint: Find out about the jet stream and prevailingwesterlies.

Hint: Learn the definitions of acyclone,warm front and cold front. How does the

cyclone affect the movement of the warm and cold air masses?

On the map on the third page, show the directions these air masses are likely to take

as they move toward and into the United States.

3. How might landforms of the United States affect the air masses moving through the

area?

Hint: The Rocky Mountains and Appalachian Mountains are major players in this

weather drama. Find out about upslope and downslope winds and how they

affect the movement of air.

Hint: Where are there no barriers to the movement of air?

4. What is a cold front and what is a warm front? What happens when the two airmasses collide?

5. Think back to what you know about how tornadoes form. Based on information

about the formation of cumulonimbus clouds, why does an occluded front create

excellent conditions for the formation of severe thunderstorms and, eventually, torna-

does?

6. Collisions between cold, dry air masses and warm, moist air masses take place in the

Great Plains. This part of the United States is sometimes called Tornado Alley.

Compare an alley in your town to Tornado Alley. How are they similar?

7. Tornado season tends to move north with the sun. That is, tornado season starts

earlier in the southern part of Tornado Alley than in its northern regions. Why is

spring the most active time for tornadoes? Use the same reasoning to explain why

the southeastern states sometimes have a mini-tornado season in the fall.


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A Cartographers Guide toTornadoesPage 2 of 3

A CARTOGRAPHERS GUIDE TO TORNADOESMasters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?




Resources: Think Quest: Thunderstorms and Tornadoes

(http://library.thinkquest.org/C0112425/stu_thundertornado.htm)

USA Today: Weather and Climate Science: Thunderstorms

(http://www.usatoday.com/weather/resources/basics/thunderstorms.htm)

The National Weather Servie: Tornado Climatology

(http://lwf.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html)

The National Weather Service: F5 Tornadoes of the United States

(http://www.spc.noaa.gov/faq/tornado/f5torns.html)

Physical Geography

(http://www.physicalgeography.net/fundamentals/7t.html)

The National Weather Service: Jetstream: An Online School for Weather

(http://www.srh.weather.gov/jetstream/matrix.htm)

Weather Patterns: Chapter 17 (a slide presentation by Cobb County Schools in

Georgia)

(http://www.cobb.k12.ga.us/~dickerson/Weather%20Patterns%20Chapter

%2017.ppt)

The Weather Channel: Special ReportsTornado! (http://www.weather.com/news

center/specialreports/tornado/index.html)

National Severe Storms Laboratory, Tornadoes: Natures Most Violent Storms(http://www.nssl.noaa.gov/edu/safety/tornadoguide.html/)

The Why FilesTornadoes (pages 15)

(http://whyfiles.org/013tornado/index.html)


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Tornado MappingPage 1 of 1

Name ________________________________________________________________________

TORNADO MAPPINGMasters of Disaster Tornadoes, Tornado Science, Lesson Plan 1/Why and Where Do Tornadoes Form?




Flint, Michigan

June 8, 1953

115 killed

Poplar Bluff, Missouri

May 8, 1997

88 killed

Xenia, Ohio

April 4, 1974

34 killed

Wichita Falls, Texas

April 10, 1979

45 killed

Waco, Texas

May 11, 1953

114 killed

Worcester,

Massachusetts

June 9, 1953

94 killed

The Tri-State Tornado

March 18, 1925

747 killed

Purvis, MississippiApril 23, 190824 tornadoes; 55 killed

Widespread OutbreakNovember 2123, 1992

26 killed

Palm Sunday OutbreakMarch 2728, 199442 killed(20 in Piedmont, Alabama)

Super Outbreak

April 34, 1974

13 states; 148 tornadoes

315 killed

Texas to Kansas

April 9, 1947

181 killed in Glazier, Texas

Arkansas

Outbreak

March 1, 1997

27 killed

Oklahoma to

Kansas

May 3, 1999

48 killed

The Dixie OutbreakApril 2324, 1908

16 tornadoes

320 deaths

Adapted from The Weather Channels The Weather Classroom.

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3 3

3

4

62 7

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