Weather and Climate Unit
Part 3: Predicting the Weather
The unequal heating and cooling of the Earth’s surface
causes our weather and climate differences.
Key Learning:
What causes weather and
climate differences?
Unit Essential Question:
Weather and Climate Unit
Part 3: Predicting the Weather
Concept: Predicting the Weather
Lesson Essential Questions:
1. What factors influence the
weather in the United States?
2. How do we use weather data to
make short term weather
predictions?
3. How can we use weather maps to
make weather forecasts?
You will be able to
answer these questions
by the end of Part 3
Vocabulary:
High Pressure System
Low Pressure System
Air Mass
Fronts/Frontal Boundary
You should already know what
these words mean. You will be
able to use them in your
responses and discussions
throughout the unit
Weather and Climate Unit
Part 3: Predicting the Weather
Homework Assignment # 8
In the Weather and Climate readings and assignments…
Read pages 26-28 and complete
the assignment on page 28
Weather and Climate Unit
Part 3: Predicting the Weather
Warm Up # 1: Now that you understand the ins and outs of
weather, what are the important factors you must look at to
describe the weather and to make future weather predictions?
Weather and Climate Unit
Part 3: Predicting the Weather
Weather and Climate Unit
Part 3: Predicting the Weather
Air Mass
mT
mP
cT
cP
Where it forms
Temperature
Humidity
Weather and Climate Unit
Part 3: Predicting the Weather
Type of Front
Cold Front
Warm Front
Occluded Front
Stationary Front
How it forms
Mass of cold air meets
and replaces mass of
warm air
Mass of warm air
overtakes cold air mass
and moves over it
Cold front overtakes a
warm front
Warm air mass meets
cold air mass and no
movement occurs
Weather
Violent storms
followed by good
weather
Fast moving 2-5
hrs
Rain and showers
followed by hot,
humid weather
Slow moving-2
days
Less extreme
weather than cold
or warm fronts
Rain may fall for
many days.
Weather and Climate Unit
Part 3: Predicting the Weather
Weather and Climate Unit
Part 3: Predicting the Weather
Warm Front: Mass of warm air overtakes cold air
Clouds: cirrus are seen first, then cirrostratus, then altostratus, and
finally nimbostratus.
7 things that happen as a warm front passes along the ground:
1. Temperature increases
2. Pressure decreases
3. Wind direction and speed change
4. Winds ahead of the warm front generally blow from east-southeast,
while behind the front, winds shift and blow from south-southwest.
5. Moves northeastward
6. Movement is slow (about 2 days)
7. Weather you usually get with a warm front is steady rain and showers
Weather and Climate Unit
Part 3: Predicting the Weather
Cold Front: Mass of cold air meets and replaces mass of warm air
Clouds: First cumulus, then altocumulus, then finally cumulonimbus.
5 things that happen as a cold front passes along the ground
1. Temperature decreases
2. Pressure increases
3. Winds are from the north-northwest
4. Weather associated with a cold front is stormy.
5. Speed of a cold front: is 2-5 hours, stormy weather followed by cool dry
conditions
Weather and Climate Unit
Part 3: Predicting the Weather
You will now watch a demonstration on how fronts
work. Pay attention to what happens to the hot
water mass and the cold water mass. You will have
to describe what happens (in terms of weather)
after the demonstration.
Weather and Climate Unit
Part 3: Predicting the Weather
Complete Summary # 1: Look at the satellite image of a pressure
system/front moving west to east along the eastern United States.
Complete the paragraph below.
Weather and Climate Unit
Part 3: Predicting the Weather
Warm Up # 2: How are weather maps useful in determining
weather forecasts?
Weather and Climate Unit
Part 3: Predicting the Weather
Weather Maps
Draw today’s weather map of the United States. Be sure to include any symbols
you see. You should use color wherever possible! Then answer the questions.
http://weather.unisys.com/index.php
Weather and Climate Unit
Part 3: Predicting the Weather
Warm Up # 3: Draw a station model to represent the current
weather conditions.
Weather and Climate Unit
Part 3: Predicting the Weather
Analyzing Weather Data
I have been collecting a month’s worth
of weather data. Analyze that data by
completing the questions and providing
evidence from the weather log.
Your group will then be responsible for
drawing 4 days’ worth of station models.
Weather and Climate Unit
Part 3: Predicting the Weather
Weather and Climate Unit
Part 3: Predicting the Weather
Complete Summary # 2: Look at the data for three different
locations. Use the three sets of data to make a 24-hour forecast
for each location. (Some hints are provided below)
Location Wind
Pressure Press.
Direction (mb)
Change
Clouds
Temp. (F)
Change
Rel. Hum.
Change
1
S-SE
1020
1017
Cirrus to
Altostratus
16 to 18
91 % to
98%
2
NW
1007
1011
Cumulonimbus Steady at 90% to
to cumulus
10
79%
3
SWNW
1020
1020
Cumulus
12 to 13
84% to
76%
 Rising pressure brings better weather and fair skies.
 Falling pressure brings poor weather
 The closer the temperature and dew point, the greater the humidity and
greater likelihood of precipitation
 The further apart the temperature and dew point, the drier the air and
greater likelihood of fair weather
 Wind shifts to the east in Delaware often indicate upcoming rainy
weather
 Clouds changing from high cirrus to lower clouds indicate warm fronts
 Clouds changing from cumulonimbus to cumulus indicate cold front
weather