Air Masses and Fronts

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Air Masses and Fronts
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Air Masses

• Air masses have the same properties as the
  surface over which it develops
• Maritime Wet mP wet/cold
• Continental Dry cP dry/cold
• Polar Cold mT wet/warm
• Tropical Warm cT dry/warm

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Air Masses in North America
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Fronts

• A front is the boundary where two air masses
  meet.
• Types of fronts
• Warm Front
• Cold Front
• Occluded Front
• Stationary Front

WARM AIR
FRONT
COLD AIR
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Warm Front

• Warm air slides over departing cold air.
• Brings drizzle followed by clear and warmer
  weather

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Cold Front

• Cold air pushes under a warm air mass.
• Warm air rises quickly.
• Brings heavy rain followed by cooler weather.

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Occluded Front

• Two cold air masses merge and force warm air
  between them to rise quickly.
• Brings cooler temperatures and large amounts of
  rain and snow.

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Stationary Front

• Warm and cold air meet but remain separated.
• Brings many days of cloudy wet weather.

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Cyclones and Anticyclones

• Areas of HIGH and LOW pressure
• Cyclone LOW PRESSURE spin counterclockwise
  associated with storms and precipitation
• Anticyclone HIGH PRESSURE spin clockwise
  associated with fair weather.

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Cyclones and Anticyclones in the USA
Rising air in CYCLONE (Low pressure) forms clouds
and rain. Falling air in an ANTICYCLONE (High
pressure) forms dry clear weather.
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Fronts - Video