Air Masses and Fronts

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Air Masses and Fronts
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Air Masses

• Air masses take on the characteristics of the
  area where they form.
• Air masses are classified according to their
  temperature and moisture content
• Warm air forms over tropical regions near the
  equator.
• T- Tropical
• Cold air forms over polar regions.
• P- Polar
• Wet air masses form over water
• m- maritime
• Dry air masses from over land.
• c- continental

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Air masses

• Moisture content is noted by the first letter.
• m maritime wet
• c continental dry
• Temperature is noted by the second letter.
• P polar cool
• T tropical - warm

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What are the four types of air masses?

• Maritime Tropical (mT)
• Maritime Polar (mP)
• Continental Tropical (cT)
• Continental Polar (cP)

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How do air masses move?

• The prevailing westerlies are the major wind
  belts in the United States.
• Prevailing westerlies push air masses from west
  to east.

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Fronts

• A front is a boundary between two air masses of
  different density, moisture, and temperature, the
  collision often causes storms and weather
  changes.
• A front may be 15 to 200 kilometers wide and
  extend as much as 10 kilometers up to the
  troposphere.
• The kind of front that develops depends on the
  characteristics of the air masses and how they
  move.

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There are four types of fronts.

• Cold Fronts.
• Warm Fronts.
• Stationary Fronts.
• Occluded Fronts.

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Cold Fronts

• Cold air mass meets a warm air mass and pushes
  the warm air mass out of its way.
• Bring thunderstorms, rain or snow.
• Most tornadoes develop from thunderstorms on the
  edge of a cold front.
• Cold fronts are followed by cooler drier air.

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Warm Fronts

• Warm air mass meets a cold air mass and pushes
  the cold air mass out of the way.
• Brings drizzly precipitation.
• Followed by clear warm weather.

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Stationary Fronts

• Cold air meets warm air.
• Not enough force to move either front.
• Many days of cloudy, wet weather.

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Occluded Fronts

• Warm air caught between two cold air masses.
• Brings cool temperatures with large amounts of
  rain or snow.

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Cold Front, Warm Front, Stationary Front and
Occluded Front Animation

• http//www.stevemcentee.com/animation3.html
• Click on the link above.

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Section Review Questions Answer the following
questions on the paper provided.

• 1. Describe a maritime polar (mP) air mass, in
  terms of moisture and temperature.
• 2. What is the name of an air mass that forms
  over water?
• 3. What is the name of an air mass that forms
  over land?
• 4. What is the name of an air mass that forms in
  a cold region?
• 5. What is the name of an air mass that forms in
  a warm region?
• 6. Describe a continental tropical (cT) air mass,
  Moisture and temperature.
• 7. The boundary between two air masses is called
  a ______________________.
• 8. A cold air mass meets and pushes a warm air
  mass out of the way.
• What type of front am I?
• 9. A warm air mass is trapped between to cold air
  masses.
• What type of front am I?
• 10. A warm air mass meets and pushes a cold air
  mass out of the way.
• What type of front am I?
• 11. I am a front that brings drizzly rain and am
  followed by warm clear weather. Name me
• 12. A cold air mass meets a warm air but neither
  is very strong. They are separated and many days
  of wet , cloudy weather occur.