Lightning

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Lightning
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How Lightning Forms

• The electrons in the bottom of the cloud are
  attracted to the positive atoms in the top of the
  cloud

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How Lightning Forms

• The electrons are also attracted to the positive
  atoms in other clouds and on the ground

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How Lightning Forms

• If the attraction becomes strong enough, the
  electrons may suddenly shoot in a path toward a
  group of positive atoms

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How Lightning Forms

• If you are watching the right spot at the right
  time, you will probably see the lightning flash

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What Happens When Lightning hits the Ground

• A stepped leader comes down from the cloud

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What Happens When Lightning hits the Ground

• An upward streamer shoots from the ground

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What Happens When Lightning hits the Ground

• The stepped leader and upward streamer meet,
  then...

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What Happens When Lightning hits the Ground

• the lightning of the return stroke flashes upward

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What Happens When Lightning hits the Ground

• A dart leader comes down through the channel
• A second return stroke flashes upward

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What kind of a cloud makes lightning

• Lightning can shoot out of the sides of funnel
  clouds. This photograph was taken from a video
  tape on tornadoes.

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What kind of a cloud makes lightning

• Thunderclouds are towering clouds you see during
  thunderstorms. In addition to lightning, these
  giants clouds can bring rain, sleet, snow and
  strong winds

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Thunderheads

• Thunderclouds usually form on warm, sunny days.
  The sun heats the moist air near the ground. As
  the air gets warm, it rises.
• Cumulus clouds form

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Thunderheads

• Sometimes a few cumulus clouds join together
• The clouds grow larger and larger
• A new cloud shape begins to take shape.

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Thunderheads

• The growing cloud pulls in more air.
• The air rushes up through the center of the
  cloud, like smoke up a chimney

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Thunderheads

• Eventually the top of the cloud hits cold air.
• Drops of water and bits of ice form.
• The cloud darkens
• Pieces of ice grow into large balls of hail.
• The cloud is now a thunderhead

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Thunderheads

• A single thunderhead can cause a storm with
  lightning.
• A single one does not last long.
• It produces 15 to 30 minutes of storm
• As one thunderhead disappears another one forms
• 1 hour of storm could have 2 or 3 thunderheads

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Where does Lightning Happen?
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Types of lightning

• When lightning looks like a blurred streak with
  more than 1 flash in it.
• This is called ribbon lightning
• Occurs when lightning channel cuts through strong
  winds

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Types of lightning

• Ball lightning
• size of a grapefruit
• found near the ground
• has been seen inside
• colors- red, orange, yellow
• last a few seconds