LIGHTNING & MORE

  Thunderstorms are well known for creating many types of weather
  conditions.  They quickly cause rain, damaging hail, sudden temperature
  changes, strong winds, many types of lightning, and tornadoes.  They
  all have one thing in common : a moist, warm, unstable air mass.
  Thunderstorms are created when a parcel of air warms, rises, and
  continues to rise as long as it stays warmer that the surrounding air.
  This rising column forms a thunderstorm 'cell' which has many updrafts
  and creates the very existence of a full-fledged thundercloud, or more
  correctly called a 'cumulonimbus' cloud.  This cloud extends several miles
  in the air -- up to about 10 miles.  At that point it encounters the
  tropopause (a layer of our atmosphere), which causes the cloud to flatten
  out at the top and look anvil-shaped.  Inside this large cloud, the
  temperature is constantly changing, the movement is generally upward in
  the center, then downward around the outsides.  This creates large circular
  air masses that are warm at the bottom, and cold at the top.  That process
  is what creates hail -- the constant warming and freezing cycle.  The
  larger and more unstable the cloud, the more cycles the hail has made;
  thus, the larger the hail.

  Lightning, while exciting to watch, can be very dangerous to people,
  buildings, and rangeland.  If it hits a power line near the block you
  live on, you, your house, and all electronic equipment will be in danger.
  It causes houses to catch fire.  It melts, shatters, and fuses electronic
  equipment.  Turning TV's, computers, and VCR's off is no protection.  A
  spike protector is of NO protection from a close lightning strike either.
  If you want to protect your valuable equipment during a lightning storm,
  the only way to do it is to simply unplug it from the wall.

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