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LIGHTNING
- Nature's Fireworks
(Print and keep this for reference)
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What Is Lightning?
The action of rising and descending air within a thunderstorm separates positive
and negative charges. Water and ice particles also affect the distribution of electrical charge
associated with lightning. Thus, lightning results from the buildup and discharge of electrical
energy between positively and negatively charged areas. The average flash could light a 100 watt
bulb for more than 3 months. Most lightning occurs within the cloud or between the cloud and ground.
Your chances of being struck by lightning are estimated to be 1 in 600,000 but could be reduced
by following safety rules. Most lightning deaths and injuries occur when people are caught
outdoors and occur in the summer months and during the afternoon and early evening when most
thunderstorms are active. 100,000 thunderstorms occur in the U.S. every year. The air near a lightning strike is heated to 50,000 deg.F - hotter
than the surface of the sun! The rapid heating and cooling of air near the lightning channel
causes a shock wave that results in Thunder. Many fires in the western U.S. and
Alaska are started by lightning. In the past decade, over 15,000 lightning induced fires
nationwide have resulted in several hundred million dollars a year in damage and the loss of
2 million acres of forest.
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Type |
Types of Lightning |
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Forked |
Smaller electrical arcs branching off from the main bolt. |
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Streak |
Lightning that looks like a single line of
light |
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Chain |
Lightning that appears to break into a dashed line
as it fades. |
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Ball |
A
fiery ball of light that lasts only a
few seconds |
| Myth |
Myths and Facts about Lightning |
| Myth 1 |
If it is not raining there is no danger from lightning |
| Fact 1 |
Lightning often strikes outside of heavy rain and may occur as far as ten miles away from any rainfall. |
| Myth 2 |
The rubber soled shoes or rubber tires on a car will protect you from being struck by lightning. |
Fact 2
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These provide NO protection. However, the steel frame of a hard-topped
vehicle provides increased protection if you are not touching any metal. Although you may be injured if lightning
strikes the vehicle, you are much safer inside a vehicle than outside. |
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| Myth 3 |
People struck by lightning carry an electrical charge and should not
be touched. |
| Fact 3 |
Lightning strike victims carry no electrical charge and should be
attended to IMMEDIATELY. |
| Myth 4 |
"Heat lightning" occurs after very hot summer days and poses no threat.
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| Fact 4 |
Heat lightning is actually lightning from a thunderstorm too far away for thunder
to be heard. However, the storm may be moving in your direction! So be alert! |
Which Way Does Lightning Travel? A cloud-to-ground lightning strike begins as an invisible channel of electrically
charged air moving from the cloud toward the ground. When one channel nears an object on the ground, a powerful surge of
electricity from the ground moves UPWARD to the cloud and produces the visible lightning strike!
Thunderstorm and Lightning Safety Precautions
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Steps |
What You Can Do
Before the
Storm
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1
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Know the area you are in and names of nearby cities as severe weather
warnings are issued on a county or city basis. |
2
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Check weather forecasts before leaving for extended periods outdoors and
always watch for signs of approaching storms. |
| 3 |
Postpone outdoor activities if thunderstorms are imminent. |
| 4 |
Check on those who may have trouble taking shelter if severe weather threatens.|
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Steps |
What You Can Do When Thunderstorms Approach
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| 1 |
If you can hear thunder you are close enough to be struck by lightning. Go
to safe shelter immediately!
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| 2 |
Move to a sturdy building or vehicle. DO NOT take shelter in small
sheds, under isolated trees or in convertible vehicles. |
| 3 |
If lightning is occurring and shelter is not available, get inside
a hard top vehicle and keep windows UP.
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| 4 |
Get out of boats and away from water.|
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| 5 |
Telephone lines and metal pipes conduct electricity - unplug
appliances not necessary for obtaining weather information, avoid using the telephone or any
electrical appliances, using phones ONLY in an emergency. |
| 6 |
Do not take a bath or shower. Turn off air conditioners
as power surges can overload compressors. |
| 7 |
Get to higher ground if flash flooding or flooding is possible. |
| Steps |
What You Can Do
If Caught Outdoors and No Shelter is
Nearby |
| 1 |
Find a low spot away from trees, fences and poles,
clotheslines, metal pipes and rails.
In a forest, seek shelter in a low area under a thick growth of small trees. Get off or away
from open water, tractors, metal equipment, bikes, motorcycles or golf carts. Make sure the place you pick is not subject to flooding. |
| 2 |
If you are in the woods, take shelter under shorter
trees. The location of the largest number of lightning fatalities is in the vicinity of relatively
isolated trees or cactuses, like a golf course or desert park. Because the electrical charges
tend to concentrate in upward projecting objects, standing underneath an isolated tree or a utility
pole is not safe. If you are in a group in the open, spread out, keeping people several yards
apart. |
| 3 |
If you feel your skin tingle or hair stand on end, squat low to the
ground on the balls of your feet. Place your hands on your knees with your head between them. Make yourself
the smallest target possible and minimize contact with the ground. Do NOT lie flat on the ground. |
| 4 |
If you are swimming or boating get to land and find
shelter inside a large building, a house or an all-metal (non-convertible) automobile
IMMEDIATELY! Do not use the telephone and if in the house or building stay
away from metal pipes and bath fixtures as lightning has been known to come through these.
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Go to this reference for food and other supplies needed for
Sources: National Oceanic and Atmospheric Administration (NOAA), U.S. Dept. of Commerce,
National Weather Service,
Federal Emergency Management Agency, American Red Cross
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