Description of a Warm Front

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Description of a Warm Front
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Description of a Warm Front

• A warm front is created by a warm air mass moving
  into a cooler area.
• Since the warm air is less dense than the cold
  air, it rises up over the cold air rather than
  pushing it aside as a cold front does.
• As the air rises, it cools and water condenses
  out of it.

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Description of a Warm Front

• Examine the diagram on your sheet.
• This will give you an indication of what an
  approaching warm front looks like.
• A day or two before the arrival of a warm front,
  the previously clear skies get a few wispy cirrus
  clouds.
• These clouds thicken, covering more of the sky.

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Description of a Warm Front

• They move lower until a layer of altostratus
  clouds covers the sky like a featureless grey
  blanket.
• Eventually the clouds are so thick that rain or
  snow begins.
• As the cloud base gets lower, the clouds become
  nimbostratus clouds.

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Description of a Warm Front

• If it is very cold, freezing rain or sleet might
  develop.
• At about the time that the precipitation stops,
  the temperature rises.

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Description of a Warm Front