9.1.5.8. Thunderstorms and Tornadoes

Other severe local storms are thunderstorms and tornadoes. They are of short duration, occurring over a small area but are violent. Thunderstorms are caused by intense convection on moist hot days.

Thunderstorms are severe local storms that can occur quickly and are characterized by violent weather, such as heavy rain, lightning, and thunder. They are typically brief but can be intense and cause significant damage. The primary cause of thunderstorms is intense convection, which happens on hot, moist days. Convection is the process where warm air rises, creating vertical clouds that can develop into thunderstorms.

Imagine a boiling pot of water. As the water heats from the bottom, bubbles of steam start to rise to the surface, just like warm air rises in a thunderstorm. When conditions are right, that rising warm air can form dense, towering clouds—similar to the steam escaping from the pot.

A thunderstorm is a well-grown cumulonimbus cloud producing thunder and lightening. When the clouds extend to heights where sub-zero temperature prevails, hails are formed and they come down as hailstorm. If there is insufficient moisture, a thunderstorm can generate dust-storms.

Thunderstorms are often associated with cumulonimbus clouds, which are tall, dense clouds capable of producing intense weather phenomena. If the cloud rises high enough to reach freezing temperatures, hail can form. Hailstones are created when updrafts in the storm carry water droplets upward, where they freeze and combine with other droplets. Conversely, if moisture is lacking, thunderstorms can result in dust storms instead of precipitation.

Think of a thunderstorm as a giant brewing pot. The cumulonimbus cloud is like a tall mountain, and as it gets taller, the temperature at its peak lowers, leading to hail, just like ice forming on the top of a mountain. If there's not enough water in the pot, instead of steam (rain), you might end up with a dry, dusty situation (dust storm).

A thunderstorm is characterized by intense updraft of rising warm air, which causes the clouds to grow bigger and rise to greater height. This causes precipitation. Later, downdraft brings down to earth the cool air and the rain.

The life cycle of a thunderstorm starts with warm air rising quickly, creating strong updrafts that help the storm grow. As the storm matures, it produces heavy rainfall. Once the storm has released much of its energy, downdrafts form and cool air descends. This process can bring about the end of the storm as the rainfall decreases, and the storm dissipates.

Imagine a balloon being filled with air. The more air you add, the bigger the balloon gets until it finally 'pops'—this is similar to how a thunderstorm builds up energy. Once enough energy is released as rain, cool air pushes down like a deflating balloon.

From severe thunderstorms sometimes spiraling wind descends like a trunk of an elephant with great force, with very low pressure at the centre, causing massive destruction on its way. Such a phenomenon is called a tornado. Tornadoes generally occur in middle latitudes. The tornado over the sea is called water spouts.

Tornadoes form when strong thunderstorms create a rotating column of air that descends to the ground. The intense differences in pressure between the inside of the tornado and the surrounding environment result in destructive winds. Tornadoes are more common in regions with open land and are often found in middle latitudes. When this phenomenon happens over water, it is referred to as a waterspout.

Think of a tornado like a giant vacuum cleaner. The lower pressure at the center of the tornado acts like the suction of the vacuum, pulling everything around it towards its center, resulting in destruction, similar to how a vacuum sucks up debris from the floor.

These violent storms are the manifestation of the atmosphere’s adjustments to varying energy distribution. The potential and heat energies are converted into kinetic energy in these storms and the restless atmosphere again returns to its stable state.

Thunderstorms and tornadoes are natural responses to energy imbalances in the atmosphere. When warm, moist air rises in conditions of instability, energy is released, leading to storm formation. Once the energy has been used up, the atmosphere starts to stabilize again.

Consider a person jumping on a trampoline. Initially, the person uses energy to propel themselves upward (like storms using energy). Once that energy is spent, they come back down and return to rest, illustrating how the atmosphere stabilizes after the energy of the storm has been released.

--