Severe Weather Awareness
 |
 |
 |
 |
 |
 |
 |
Today’s topic is lightning.
Lightning occurs with all thunderstorms and is what defines them as thunderstorms.
Central North Carolina faces dangers from lightning throughout the entire spring and
summer. Over the course of one year, the earth will be struck by lightning nearly 20 million
times. In a typical year there are around 500,000 lightning strikes in North Carolina
resulting in around 9 to 12 strikes per square mile in Central North Carolina. Since 1959
there have been nearly 200 reported lightning deaths in North Carolina. Unfortunately
many lightning deaths go unreported and are attributed to cardiac arrest meaning the
actual number of lightning deaths in North Carolina is probably much higher. Most
lightning deaths are the result of cardiac arrest so knowing how to respond quickly using
C.P.R. can save a lighting victims life.
Lightning results from the buildup and discharge of electrical energy between positively
and negatively charged particles. A thunderstorm builds up a huge electrical charge as
ice particles inside the storm collide and this friction will generate a static charge. These
particles of suspended ice in the thunderstorm collide as they are carried around by the
storm’s updraft and downdraft. Once the electrical charge is strong enough to travel from
the cloud to the ground, a lightning bolt is created.
A lightning bolt carries as much as 300,000 amperes and one billion volts. The air around
the lightning strike is instantly heated to 50,000 degrees. This is five times hotter than the
surface of the sun. This instantaneous heating of air around the lightning strike causes
the air molecules to explosively expand. This expansion occurs so rapidly it compresses
the air forming a shock wave similar to a sonic boom. The shock wave travels through the
atmosphere...resulting in thunder. The acoustic shockwave near the lightning strike is
strong enough to rupture the eardrums of those standing nearby.
You can use thunder to gage the distance of a lightning strike. You simply count the
number of seconds between the moment you see the flash of lightning and hear the clap
of thunder. Once you see lightning...start counting seconds. For every 5 seconds that go
by before you hear the clap of thunder...that’s one mile. Keep in mind this technique only
tells you how far away that one lightning strike was from your location. The next one could
be a lot closer. Lightning can travel as far as 10 to 12 miles from a thunderstorm. For that
reason, anytime you hear thunder or see lightning, seek shelter indoors. A car is a safe
place from lightning because of its metal frame.
Most lightning deaths occur when people are caught outside working or taking part in
some recreational activity. Because of the abundance of outdoor activities in North
Carolina...we are especially vulnerable to lightning. If you are outside...move indoors if
possible. Stay off of the telephone and stay away from windows. If caught outdoors, stay
away from trees, telephone poles, and other tall objects. When boating...try to seek safe
shelter before the storm approaches. Stay indoors for at least 30 minutes after hearing the
last clap of thunder. This should guarantee your safety.
More information about lightning can be found by visiting...
http://www.lightningsafety.noaa.gov
http://www.srh.noaa.gov/srh/jetstream
Lightning occurs with all thunderstorms and is what defines them as thunderstorms.
Central North Carolina faces dangers from lightning throughout the entire spring and
summer. Over the course of one year, the earth will be struck by lightning nearly 20 million
times. In a typical year there are around 500,000 lightning strikes in North Carolina
resulting in around 9 to 12 strikes per square mile in Central North Carolina. Since 1959
there have been nearly 200 reported lightning deaths in North Carolina. Unfortunately
many lightning deaths go unreported and are attributed to cardiac arrest meaning the
actual number of lightning deaths in North Carolina is probably much higher. Most
lightning deaths are the result of cardiac arrest so knowing how to respond quickly using
C.P.R. can save a lighting victims life.
Lightning results from the buildup and discharge of electrical energy between positively
and negatively charged particles. A thunderstorm builds up a huge electrical charge as
ice particles inside the storm collide and this friction will generate a static charge. These
particles of suspended ice in the thunderstorm collide as they are carried around by the
storm’s updraft and downdraft. Once the electrical charge is strong enough to travel from
the cloud to the ground, a lightning bolt is created.
A lightning bolt carries as much as 300,000 amperes and one billion volts. The air around
the lightning strike is instantly heated to 50,000 degrees. This is five times hotter than the
surface of the sun. This instantaneous heating of air around the lightning strike causes
the air molecules to explosively expand. This expansion occurs so rapidly it compresses
the air forming a shock wave similar to a sonic boom. The shock wave travels through the
atmosphere...resulting in thunder. The acoustic shockwave near the lightning strike is
strong enough to rupture the eardrums of those standing nearby.
You can use thunder to gage the distance of a lightning strike. You simply count the
number of seconds between the moment you see the flash of lightning and hear the clap
of thunder. Once you see lightning...start counting seconds. For every 5 seconds that go
by before you hear the clap of thunder...that’s one mile. Keep in mind this technique only
tells you how far away that one lightning strike was from your location. The next one could
be a lot closer. Lightning can travel as far as 10 to 12 miles from a thunderstorm. For that
reason, anytime you hear thunder or see lightning, seek shelter indoors. A car is a safe
place from lightning because of its metal frame.
Most lightning deaths occur when people are caught outside working or taking part in
some recreational activity. Because of the abundance of outdoor activities in North
Carolina...we are especially vulnerable to lightning. If you are outside...move indoors if
possible. Stay off of the telephone and stay away from windows. If caught outdoors, stay
away from trees, telephone poles, and other tall objects. When boating...try to seek safe
shelter before the storm approaches. Stay indoors for at least 30 minutes after hearing the
last clap of thunder. This should guarantee your safety.
More information about lightning can be found by visiting...
http://www.lightningsafety.noaa.gov
http://www.srh.noaa.gov/srh/jetstream
