Download Activity 1

Severe Weather
After a quick flash of light, you brace yourself for the boom of the thunder. Another thunderstorm seems to have
moved over your area. “Hurry up and get off that computer!” your mom yells up to you. You quickly print out the
latest email you’ve received from your science teacher, and shut down the computer before the next flash of
lightning.
From: [email protected]
To: [email protected]
Subject: Severe Weather
Good Morning Science Students! I’m away from school, right now. I planned a trip to Tornado Alley to check out the
weather. Whew, those clouds outside are looking really dark out there. I believe a storm’s coming this way. I just
realized you haven’t researched Severe Storms. I have attached a few activities for you to complete while I’m away. In
this investigation, you will uncover the mystery of storms and determine just what it takes for Thunderstorms and
Tornadoes to form.
Objective
When you have completed this investigation, you will be able to examine characteristics of thunderstorms and
tornadoes in order to describe the conditions necessary for their formation.
Activity 1
1.
Observe the pictures and video footage of various storms provided by your teacher.
2. Predict the atmospheric ingredients necessary for thunderstorms to occur. Record you response in Chart
1, “Recipe for a Thunderstorm.”
Chart 1
Recipe for a Thunderstorm
Predicted Atmospheric Ingredients
Actual Atmospheric Ingredients
Activity 2
So, now that you have observed some pictures and videos of real-life storms, it is time to read about the conditions necessary for storms to
form.
1.
Read each statement below. If you think the statement is true, place a “” in the Before Reading Agree column. If you think the statement is false,
place a “” in the Before Reading Disagree column.
Before Reading
Agree
Disagree
________
________
After Reading
1.
A storm is a violent disturbance in the atmosphere.
Agree
Disagree
________
________
Justification from text:
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Agree
Disagree
________
________
2. Storms occur when air pressure is steady.
Agree
Disagree
________
________
Justification from text:
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Agree
Disagree
________
________
3. Thunderstorms form when warm air pushes upward at a warm front.
Agree
Disagree
________
________
Justification from text:
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Before Reading
Agree
Disagree
________
________
After Reading
4. Thunderstorms and tornadoes form in the same types of clouds.
Agree
Disagree
________
________
Justification from text:
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Agree
Disagree
________
________
5. A tornado is more likely to form when a cold, dry air mass from the Gulf of Mexico
Agree
Disagree
________
________
meets a warm, moist air mass from Canada.
Justification from text:
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Agree
Disagree
________
________
6. Thunderstorms are more likely to occur in winter and spring during the early
Agree
Disagree
________
________
morning when the ground is cooler.
Justification from text:
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Activity 3
1.
Read pages 83-88 in Prentice Hall: Science Explorer, Weather and Climate to gather information about the
formation of thunderstorms and tornadoes.
2. Refer to the predictions you made in the “Before Reading” column in Activity 2. Based on what you have read,
determine if your predictions were correct or incorrect. If you now believe the statement is true, place a “”
in the “After Reading” Agree column. If you now believe the statement is false, place a “” in the “After
Reading” Disagree column. Justify your choices with support from the text.
3. Review the prediction you made in Activity 1 regarding the atmospheric conditions necessary for the formation
of a thunderstorm. Complete the “Actual Atmospheric Ingredients” box based on the information from the
reading.
CLASS DISCUSSION
Observe the animation describing the formation of a tornado. Complete the sequence chain to describe the
conditions that occur which may lead to the development of a tornado.
 _________________ at the surface
 _________________ air from
blow one ____________________;
the surface _______________
_________________ higher up
 As it ____________, the water
blow the
vapor ___________________
______________________
to form __________________
direction.

The difference creates a
_________________________ ,
____________________ mass of air
 _________________ warm
____________ creates an
___________________
which pulls the rotating air
mass _________________
 Air from inner rotation may drop
_________________________ out of the cloud
where air pressure is ______________________
OR
 the tornado may form from the ground
__________________________
Analysis
The American Meteorology Society's Glossary of Weather and Climate defines Tornado Alley as: "The
area of the United States in which tornadoes are most frequent. It encompasses the great lowland areas
of the Mississippi, the Ohio, and lower Missouri River Valleys. Although no state is entirely free of
tornadoes, they are most frequent in the Plains area between the Rocky Mountains and Appalachians."
Depending on the time of year, the southern and northern borders
of Tornado Alley extend from about central Texas to Nebraska and
Iowa. This region is where tornadoes spin up most frequently and
where most monster, mile-wide twisters roam.
The map shows the areas included in “Tornado Alley.”
Adapted from: http://www.usatoday.com/weather/wtorally.htm and
http://library.thinkquest.org/C001472/neen/tornadoes/alley.content.html
1.
Explain why tornadoes would be more likely to form in the area known as “Tornado Alley.” Use information from
the investigation to support your response.
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Your Science Teacher sends you another email from Tornado Alley. She is now traveling with a team of local
storm chasers. As she was typing the email, a storm quickly emerged so she sent a message.
From: [email protected]
To: [email protected]
Subject: On the Scene in Tornado Alley
Hi Class:
I wish you all were here! You wouldn’t believe the weather conditions here. This afternoon heat and humidity is
overwhelming! There are large cumulonimbus clouds overhead. The sky is getting dark and the winds appear to be
picking up. Whoa! Oh my…
After reading the email you become worried. You quickly consider the research you’ve conducted on Severe
Weather to determine if your teacher is in danger.
2. Determine if the weather conditions described in your science teacher’s email are favorable for the formation
of a tornado. Use information from the email and your research to support your response.
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