Lightning Awareness and Safety
Even though it has been a slow transition from winter into spring this year, summer will be here before you know it. And as we spend more time outdoors, we can't forget about the dangers associated with thunderstorms. Meteorologists have a general idea of where and when thunderstorms will occur on a given day, however, it's the localized impacts of a thunderstorm that make them tough to forecast. Lightning, for instance, is particularly dangerous, localized, and difficult to predict, so let's review some safety tips.
First off, lightning occurs as a means of equalizing a thunderstorm's charge separation (see image below, courtesy of NOAA). There are four types of lightning: cloud to ground (most harmful to people), cloud to cloud, intra cloud and cloud to air. If you see an approaching thunderstorm, be aware that a storm only needs to be within 10 to 15 miles before lightning becomes dangerous. If you what to estimate lightning distance do this: when you see a flash, count the number of seconds until you hear thunder and divide by 5. The result is the distance to the lightning strike. But, one should never mess around with lightning. If you hear thunder, then you are close enough to get struck by lightning. Remember, when thunder roars, go indoors.
So how do you protect yourself from lightning? Indoors is the safest place during a thunderstorm. When inside, avoid corded phones, electrical equipment, and plumbing. Avoid contact with water such as taking a shower, washing dishes, or doing laundry. Stay away from windows, doors, porches, and even the garage. Also, do not lie on concrete floors or lean on concrete walls. The most interior room on the lowest level of a house is the safest place (ex. closet, pantry) during a thunderstorm.
If you are outdoors, keep moving to find a safe shelter. There is NO safe place outside in a thunderstorm. If you absolutely cannot find a shelter, stay away from high hills, trees (especially isolated ones), poles and fence rows. Keep in mind baseball dugouts (or similar shelters), highway overpasses, and bodies of water do not protect you from lightning. Cars with hard top roofs do provide safety because the electricity from the lightning will go around the metal frame into the ground; therefore, do not lean against car doors during a thunderstorm.
Here are a few facts about lightning. The temperature of a lightning bolt is 54,000 degrees Fahrenheit, that's five times hotter than the surface of the sun. Lightning flashes about 3 million times a day around the world, or 40 times a second. The United States averages about 22 million lightning strikes per year. Florida is the leading state averaging 1.4 million strikes each year. Unfortunately, lightning kills about 2000 people every year, so again, stay inside during a thunderstorm.
Finally, we get a lot of questions about what exactly is heat lightning. Heat lightning is not the result of a very hot day at a particular location. In fact, it is an actual thunderstorm that is so far away that a person can see the lightning from it, but not hear the thunder. This is because light can travel farther than sound, so the sound of the thunder dissipates before it reaches the observer.