At any given moment there are 1,800 thunderstorms in progress somewhere on the earth. This amounts to 16 million storms each year.
An estimated 25 million cloud-to-ground lightning flashes strike in the U.S. per year.
The sound of thunder is caused by rapid expansion of heated air as channels for lightning within storms warm rapidly to 50,000 degrees Fahrenheit.
Light travels faster than sound so thunder is heard only AFTER lightning has struck.
If you see lightning and hear thunder at the same time, lightning is in your area.
Ice within a cloud seems to be a key element in the development of lightning.
Ice particles -- that vary in size from small ice crystals to larger hailstones -- become electrically charged as they collide within a storm.
A moving thunderstorm gathers another pool of positively charged particles along the ground, traveling with the storm. Positively charged particles rise up taller objects such as trees, houses, telephone poles and people in open spaces.
If your hair stands on end, it could be a sign you are about to be a lightning target, due to positively charged particles.
Some lightning can strike as far as 10 miles ahead of a thunderstorm - or 10 miles behind one. Scientists have no way to forecast the location or time of the next strike of lightning.
For additional lightning safety information, visit the NOAA Lightning Safety webpage.