Atmosphere And Weather

Calculating the Distance of a Thunderstorm

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"Calculating the Distance of a Thunderstorm"
Caption: Thunderstorm
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A thunderstorm is some type of turbulent weather formations that may develop lightning and thunder. Thunderstorms are usually accompanied by very strong winds, heavy rain and occasionally hail or snow. A thunderstorm may stem from a single cumulonimbus cloud or include several rotating thunderstorms known as supercells. Thunderstorms are formed by the rapid rising of warm, moist air in the atmosphere. Thunderstorms tend to develop in zones of unequal surface heating, inside warm, moist air masses and frontal zones. The distance of a thunderstorm is usually determined by counting the seconds elapsed from the moment of lightning to the moment in which thunder is heard.

Cloud formation

Thunderstorm clouds form when the Sun´s radiation heats the Earth´s crust, causing warm air to rise into the Earth´s atmosphere. As the warm air rises, it cools and condenses into water droplets, releasing large quantities of latent heat. This maintains the rising air inside the cloud warmer than the surrounding air. The warmer rising air pushes the cloud which keeps growing up in the unstable atmosphere. Over time, the cloud may show extensive vertical expansion, growing into an enormous towering cumulonimbus cloud, which in a matter of minutes, may extend for more than 12 km (40,000 ft.) in height and several km in diameter.

Stages in a thunderstorm

Typically all thunderstorms undergo three different developing stages; a developing stage, a mature stage and a dissipating stage. During the developing stage, warm masses of moisture are raised into the atmosphere; the moisture cools rapidly and condenses into droplets, releasing latent heat and appearing as cumulus clouds in the sky. In the mature stage heated air continues rising until reaching the tropopause, where it is carried horizontally, acquiring an anvil shape. In the mature stage updrafts and downdrafts reach their greatest strength in the central part of the cloud, producing rain and lightning and a gust front at the surface. The dissipating stage occurs when the updrafts weaken, anywhere from 15-30 minutes after the mature stage.

Lightning and thunder

Lightning is produced inside a thunderstorm when opposite electrical charges produce a spark of electricity. Lightning may occur inside a cloud, from one cloud to another or from a cloud to the ground. The lightning stroke can produce temperatures that can heat the surrounding air through which it travels to about 30,000 ºC (54,000 ºF), accounting to 5 times hotter than the temperature over the surface of the Sun. these extreme temperatures cause the atmospheric air to expand explosively, producing a shock wave that turns into a roaring sound wave that expands outwards in every direction from the lightning.

Distance of a thunderstorm

The speed of sound in the lower atmosphere under the right atmospheric conditions is 330 meters/second (1 mile/5 seconds) if you want to determine the distance of a thunderstorm at the region of a lightning flash, you may need to count the seconds elapsed from the moment of lightning to the moment the sound of thunder reaches your ears. This will give you the distance in meters or miles. For example, if you hear the thunder after three seconds, then, the distance of the thunderstorm at the exact area of lightning is 1 km or 0.62 miles. A thunder boom usually travels one mile every five seconds.

Thunder under normal atmospheric conditions may be audible within an average distance of 8-10 km (5-6.2 miles). Sonic booms are produced by airplanes that exceed the speed of sound, producing a shock wave that travels outwards. Sonic booms are usually mistaken by thunder. Prevailing strong winds and low atmospheric temperatures may alter these estimations significantly. According to, the speed of sound in air is much less than the speed of light; therefore, it is possible to calculate the distance of a thunderstorm, as long as you can observe the lightning and the storm within a range distance of 8-10 kilometers (5-6.2 miles), under normal atmospheric conditions.

More about this author: Jose Juan Gutierrez

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