Thunderstorms and Lightning

03/14/2012
Today we will be looking at Thunderstorms and Lightning! WHAT IS A THUNDERSTORM1/2 A thunderstorm is formed from a combination of moisture, rapidly rising warm air and a force capable of lifting air such as a warm and cold front, a sea breeze or a mountain. All thunderstorms contain lightning. Thunderstorms may occur singly, in clusters or in lines. Thus, it is possible for several thunderstorms to affect one location in the course of a few hours. Some of the most severe weather occurs when a single thunderstorm affects one location for an extended time. DID YOU KNOW... - At any given moment, nearly 1,800 thunderstorms are in progress over the surface of the earth. - On average, the United States gets 100,000 thunderstorms each year. Approximately 1,000 tornadoes develop from these storms. - Large hail results in nearly $1 billion in damage to property and crops. - Straight-line winds exceeding 100 mph are responsible for most thunderstorm damage. HOW FAR AWAY IS THE THUNDERSTORM1/2 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. REMEMBER THE 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. LIGHTNING Lightning is fascinating to watch but also extremely dangerous. In the United States, there are about 25 million lightning flashes every year. Understanding the dangers of lightning is important so that you can get to a safe place when thunderstorms threaten. If you hear thunder--even a distant rumble or a crackling aloft--you are already in danger of becoming a lightning victim. WHAT IS LIGHTNING1/2 Lightning is an electrical discharge that results from the buildup of positive and negative charges within a thunderstorm. When the buildup becomes strong enough, lightning appears as a "bolt". This flash of light usually occurs within the clouds or between the clouds and the ground. A bolt of lightning reaches a temperature approaching 50,000 degrees Fahrenheit in a split second. The rapid heating and cooling of air near the lightning causes thunder. DID YOU KNOW. * Lightning bolts can strike up to 10 miles from their parent cloud into areas with blue skies. This is called a Bolt from the Blue. * Temperature of lightning: estimated 50,000 F (5 times hotter than the surface of the sun) SAFE SHELTERS * Substantial building-fully enclosed with a roof, walls and floor, and has plumbing or wiring. * Stay away from showers, sinks, bath tubs, & electronic equipment. * Enclosed metal vehicle - metaltopped vehicle such as a hard-topped car, minivan, bus, truck, etc. * Do not use electronic devices. UNSAFE SHELTERS & VEHICLES * Unsafe Shelters -Car ports, open garages, covered patios, picnic shelters, golf shelters, tents of any kind, baseball dugouts, sheds and greenhouses. * Unsafe vehicles - golf carts, convertibles, motorcycles, etc.

Related Links:
Thunderstorms and Lightning: What you need to know to stay safe - http://bit.ly/SWAWDay3
DCEM Website - http://bit.ly/yIXuxi
DCEM Facebook Page - http://www.facebook.com/dgcoem
DCEM Twitter Page - http://www.twitter.com/dgcoem

Media Contact:
Teri Smith, Director
Emergency Management Department
785-832-5259
tsmith@douglas-county.com