1. • Draw square
• Get density activity ready
• Get out jar, green food coloring and hot plate
• Gather jars, cans, saran wrap, rubber bands,
straws and index cards for barometers

2. Bellwork
What kind of weather can we expect in the next
few days according to the map?
Us

3. Why Do We Have
Weather?

4. WHY DO WE HAVE THE WEATHER ?
• Just think about it!
• Why is there wind? Why does it blow
from one direction one day and another
the next?
• Why is it rainy one day and dry the
next?
• How come it’s cold in the winter?
• How can we have hail in the summer?
• What causes snow and freezing rain?

5. If we were to pick one term to help
explain why we have weather, what do you
think would be a good word?
You might pick heat or sun….but another
good choice would be
Convection

6. Convection: the transfer of heat,
usually in gases or liquids.

7. Convection Demo
• How does convection work?
• See if you can watch the demo
and make sense of convection

8. Warm Air - How do air molecules act?
The walls of this room are the walls of our
container.
You are all air molecules. Lots of nitrogen, some
oxygen and a little carbon dioxide.
Warm air is active. It moves around quickly and
will bounce off the walls.
Say:
I’m moving FAST.
I can hold lots of moisture.

9. Cold Air - How do air molecules act?
The walls of this room are the walls of our
container.
You are all air molecules. Lots of nitrogen, some
oxygen and a little carbon dioxide.
Cold air moves slowly. It moves around very
slowly and will move closer together.
Say:
I’m moving slowly.
I can’t hold much moisture.

10. Density???
• how close together the molecules of a substance
are or how much mass a substance has in a
given space
• Density Demo
– Hold each
– What is the size of the two canisters?
– Does one feel heavier than the other?
– Mass the two and write down the mass of each.
Suga
Flour
r

11. Which one is more dense?
How do you know?
Flour Sugar

12. After the atmosphere is warmed by radiation (sun) and
conduction, the heat is transferred throughout the
atmosphere by convection.
• Warmed air: has more
space between the
molecules, it’s less dense
and rises
• Cooled air is more dense
and tends to sink
• In general, air near the
equator tends to rise and
air near the poles tends
to sink

13. Density of Air – Square on the Floor
• Everyone stand inside • Half the class stand
the square outside the square.
• You are all air • The ones inside the
molecules (lots of square spread out.
nitrogen, some • You are warm air.
oxygen, and a little • What will you do?
carbon dioxide, etc.)
• You are cold air.
What will you do?

14. Density of Air
• Can you explain why warm air
rises with what you know
about density now?
• Can you explain why cool air
sinks with what you know
about density now?

15. How Do Clouds Form?
• First let’s review evaporation
• Evaporation: the process of a liquid becoming
a vapor (gas)
• Cut and Paste Image
• Phet: http://phet.colorado.edu/sims/states-
of-matter/states-of-matter-basics_en.jnlp

16. How Do Clouds Form?
Step 1 – Warm, moist air rises
Step 2 – That warm air hits the
cooler air in the upper atmosphere
Step 3 – When it hits the cooler air,
it condenses onto dust particles in
the air into water droplets

17. Teach Your Neighbor Using
Gestures
I’ll
Demonstrate

18. How Do Clouds Form?
Step 1 – Warm, moist air rises
Step 2 – That warm air hits the
cooler air in the upper atmosphere
Step 3 – When it hits the cooler air,
it condenses onto dust particles in
the air into water droplets

19. Did You Know?

20. How Does Air Behave?
• Cold air can hold less
moisture than warm air
• Warm air can hold more
moisture than cold air

21. Consequences of Rotation: The Coriolis
Effect - Video

22. The Weather Highways
Coriolis Effect
• Created by the
ROTATION of the Earth
• Causes the air and water
to be pushed to the right
north of the equator.
• This creates global
weather highways
• Cut and paste Coriolis
Image

23. The Westerlies
• Winds that blow from the west to the east
• most of our weather comes from the west
• Cut and Paste Global Wind Image

24. What Weather Should We Expect?

25. Trade Winds
• Winds that blow from the east to the west
• These affect the paths of hurricanes

26. Let’s break for a short review:
1.Transfer of heat in liquids or
gases_____.
2. _____ air is dense and tends to sink.
3. Cold air holds _____ moisture than
warm air.
4. The Coriolis effect causes the air and
water vapor to be pushed to the _____
to the North of the equator.

27. How did you do?
1. CONVECTION
2. COLD
3. LESS
4. RIGHT

28. Cloud in a Bottle Demo

29. Cloud in a Bottle Lab
C.H.A.M.P.S. – Group Work, Voice Level 2,
Complete Lab, Finger Signals, Jobs
1.We will add water to 1/3 of the bottle.
2.We will

30. Let’s Play a Game
• Weather Game

31. Now What?
• Ok, so we know that the weather moves
around on these highways and that warm
air rises and cold air sinks.
• But why is it sunny one day, and rainy
the next?

32. Let’s take another look at the weather
map:
• Notice that there are
H’s and L’s on the map
• There are also blue
lines with spikes and
red lines with half
circles
• Let’s take a closer
look!

33. High and Low Pressure - Video

34. High Pressure Areas
• Cooler air sinks
and is warmed
• This usually
means sunny
skies

35. Low Pressure Areas
• When warm air
rises and cools
• Precipitation
and stormy
weather

36. So, if you see a big H on the weather
map over the area you live, you can
expect fair weather.

37. When you see a big L in your area,
there will probably be stormy
weather

38. Teach Two of Your Neighbors
• Action of High Pressure: Push Down on neighbor’s
Pressure
shoulders and say:
– You are a bunch of air molecules.
– You’re experiencing a high pressure that doesn’t
allow you to rise and make clouds
– No clouds means no rain
• Action Low Pressure: Let go of his or her shoulders
Pressure
and say:
– You are still a bunch of air molecules.
– You’re experiencing a low pressure that allows
you to rise and make clouds.
– Clouds that fill up with moisture will mean rain.

39. How do Air and Water Molecules Act Under Pressure
• Half the class stand • Now, I’m going to stop
outside the square box. adding air and water
• Half the class stand inside molecules to the box and
the square box. we are going to take the
• I’m going to add air and lid off of it.
water molecules to box. • Start slowly moving to the
• Those outside move to the front of the room.
inside. • As you rise to the front,
• You are under a lot of what will you do?
pressure. • Condense and become
• You can’t rise. (no clouds) clouds.

40. Barometer
• Barometers are used by
meteorologists to keep
track of pressure in the
air.

41. Understanding the Barometer
• If you see the barometer
pointer moving downward,
what does that mean?
– The pressure is
increasing.
• If you see the barometer
pointer moving upward,
what does that mean?
– The pressure is
decreasing.

42. These highs and lows move along
the jet stream and bring us our
weather changes.
• Video

43. Jet Stream
• A fast flowing river of air found in the
atmosphere at around 12 km above the
surface of the Earth.
• They form at the boundaries of air masses
with large differences in temperature, such as
of the polar region and the warmer air to the
south.

44. Jet Stream Demo
Using: Hair Dryer, ping pong ball
•The hair dryer shoots a column of air up between
air that is also in the room.
•When I tilt the hair dryer left and right, the ping
pong ball stays in the column of air.
•Jet streams are columns of air in upper
atmosphere.
•These weather columns are like currents. These
columns of air move throughout the year.

45. Fronts and Air Masses
• Air mass: a large body of air whose
temperature and moisture are fairly
similar at a given altitude
• Fronts: boundaries separating different
air masses
• There are four different air masses
that affect the United States

46. Warm and Cold Fronts - Video

47. Ok, now we see the difference in
the air masses
• Let’s look at the different fronts and their impact on
weather
• Can you see the four different types of fronts on the map?

48. Warm Fronts
• A warm front is
warm air taking
over the cool air
• The front edge of
warm air must
“overrun” cold air
• Slow moving

50. Cold Fronts
• Cold air advances Video
into region of
warm air
• Rain and
Thunderstorms
• Clearing conditions
after front passes

51. Cold Front is Moving In – 5:28
• As the warm air was pushed up (low pressure allowed it to rise),
the warm air cooled and condensed.
• The condensed water vapor (gas) caused clouds, which could not
hold as much moisture (water vapor [gas]).
• This caused rain and thunderstorms.
• What will the weather be like after the cold front passes
through?

52. Stationary Fronts
• Surface positions
of the front do
not move
• Often a region of
clouds
• Neither the cold
or the warm front
are ‘winning’.

53. Quiz
1. Get out a sheet of paper.
2. Spread out around the room.
3. C.H.A.M.P.S.
• Voice Level of 1
• Come to my desk for help
• Quiz
• Finger Signals
• Complete the Quiz

54. 1.
• What causes a low
pressure system to
create clouds and
sometimes precipitation? L

55. 2.
• What type of
front can be
found close to
point D ?

56. 3.
• Which of these
fronts would you
expect to have
greater
precipitation,
but be short
lived as the
front passes?

57. 4.
• Give the name of
the air mass that
would have the
following
characteristics:
• cool, moist,
unstable

58. 5.
That important weather word that
refers to the transfer of heat

59. 6.
In general, air near the equator
tends to_____ ( rise or fall ).

60. 7.
________ causes air and
water to be deflected to the
right north of the equator.

61. 8.
Which of the weather highways usually
controls our weather

62. 9.
Warm air holds ( more or less )
moisture than cold air?

63. 10.
• If there is a big
H on the
H
weather map
where you live,
would you expect
fair or stormy
weather?

64. How did you do?
Let’s check the answers!

65. Answers
1. The low pressure allows the warm air to rise. As the
warm air rises, it cools. Water vapor cools and
condenses into clouds. Cold air can hold less moisture,
so eventually it might rain.
8. Westerlies
2. Cold front 9. More
3. Cold front 10. Fair
4. Maritime polar (mP)
5. Convection
6. Rise
7. Coriolis Effect

66. Predict the Weather Game
• Game

67. Centers
• Vocabulary