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LIGHTNING

 

lightning photo

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 charge.
  • 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.

second lightning photo

  • Most lightning deaths occur when people are caught outdoors.
  • Most lightning casualties occur in the summer months and during the afternoon and early evening.
  • The air near a lightning strike is heated to 50,000 degrees 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 states 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 forest acres.

* Credit for the above photos, in order, go to Warren Faidley, Weatherstock 1991, and the Phoenix Gazette *


LIGHTNING SAFETY RULES

  • Postpone outdoor activities if thunderstorms are imminent. This is your best way to avoid being caught in a dangerous situation.

  • Move to a sturdy building or car. Do not take shelter in small sheds, under isolated trees, or in convertible automobiles. Stay away from tall objects such as towers, fences, telephone poles, and power lines.

  • If lightning is occurring and a sturdy shelter is not available, get inside a hardtop automobile and keep the windows up. Avoid touching any metal.

  • Utility lines and metal pipes can conduct electricity. Unplug appliances not necessary for obtaining weather information. Avoid using the telephone or any electrical appliances. Use phones ONLY in an emergency!

  • Do not take a bath or shower during a thunderstorm.

  • Turn off air conditioners. Power surges from lightning can cause serious damage.

  • 30/30 rule - Go indoors if, after seeing lightning, you cannot count to 30 before hearing thunder. Stay indoors for 30 minutes after hearing the last clap of thunder.

  • For additional safety information, check out: www.lightningsafety.noaa.gov

IF CAUGHT OUTDOORS AND NO SHELTER IS NEARBY

  • Find a low spot away from trees, fences, and poles. Make sure the place you pick is not subject to flash flooding.

  • If you are in the woods, take shelter under the shorter trees.

  • If you feel your skin tingle or your hair stand on end, squat low to the ground on the balls of your feet. Place your hands over your ears and your head between your knees. Make yourself the smallest target possible and minimize your contact with the ground. DO NOT lie down!

  • If you are boating or swimming, get to land and find shelter immediately!

HOW FAR AWAY IS THE THUNDERSTORM?

  • Count the number of seconds between a flash of lightning and the next clap of thunder.

  • Divide this number by 5 to determine the distance to the lightning in miles.

 

LIGHTNING MYTHS AND FACTS

  • MYTH:  If it is not raining, then there is no danger from lightning.
  • FACT:  Lightning often strikes outside of heavy rain and may occur as far as 10 miles away from the rainfall.

  • MYTH:  The rubber soles of shoes or rubber tires on a car will protect you from being struck by lightning.
  • FACT:  Rubber-soled shoes and rubber tires provide NO protection from lightning. However, the steel frame of a hard-toped vehicle provides increased protection if you are not touching metal. Although you may be injured if lightning strikes your car, you are much safer inside a vehicle than outside.

  • MYTH:  People struck by lightning carry an electrical charge and should not be touched.
  • FACT:  Lightning-strike victims carry no electrical charge and should be attended to immediately. Contact your local American Red Cross chapter for information on CPR and first aid classes.

  • MYTH:  "Heat Lightning" occurs after very hot summer days and poses no threat.
  • FACT:  What is referred to as "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!

 

 

 

 

 


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