Thunder

Thunder is the sound produced by the rapid expansion and contraction of air surrounding a lightning discharge during a thunderstorm. It occurs as a result of the intense heat generated by lightning, which can reach temperatures of about 30,000 degrees Fahrenheit (16,650 degrees Celsius). This sudden increase in temperature causes the air to expand explosively, producing a shock wave that we hear as thunder. The sound typically follows the flash of lightning, with the delay between seeing the lightning and hearing the thunder varying with distance; the greater the distance, the longer the delay. Thunder can vary in loudness and duration, ranging from a sharp crack to a deep rumble, and is often used to signify the presence of an electrical storm.