DECATUR, Ill. (WAND) - Many weather sayings and proverbs have become popular over the years. Have you ever heard, when thunder roars, go indoors? Â
It is a great one to remember. Thunder is a byproduct of lightning. A lightning flash lasts on average about 30 microseconds, but the entire strike sequence can last up to a second. That is fast! So, you cannot outrun it.Â
The air is rapidly heated around the lightning bolt (50,000 degrees Fahrenheit) and then cools rapidly after it is over. The rapid expansion and contraction of heated, then cooled air creates a vacuum that air has to rush in to fill; that is the thunder we hear.Â
When we hear thunder, the lightning has already occurred, so no messing around, especially if you are in the pool. Water is an excellent conductor of electricity. Â
Approximately 1.4 billion lightning flashes occur worldwide every year. That is roughly 44 lightning strikes per second globally. The United States experiences about 25 million lightning strikes annually. Unfortunately, lightning causes around 300 injuries and about 20-30 fatalities each year in the U.S.
Once again, when thunder roars, go indoors. Â
Heat, humidity and thunderstorms are all part of this weekend's outdoor activities. The good news is that the WAND weather app has futurecast radar and is a free download.  Â
Have a happy weekend!
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