Due to unequal warming of the surface of the Earth, air constituting water droplets are lifted vertically into the atmosphere. Due to this lift, the air condenses and latent heat is released with the expansion as a result of decrease in pressure. Those condensed droplets freeze and fall back to the land along with hail and lightning.  

  The mass of an air that rotates around the centre of low pressure on a large scale is defined as cyclones. It is characterized by inward spiralling winds, rotating clockwise or anticlockwise. 

Cyclones are originated on areas of low atmospheric pressure, commonly over warm ocean waters near the equator. Formation of the low pressure zone over the surface results from the warm moist air over the ocean rises from the surface in the upward direction. A high pressure air forcefully enters into the low pressure area.

The cool air becomes warm and moist and rises again and the cycle continues.

Warm air risen upwards cools down leading to formation of cloud. This whole procedure gradually grows and becomes fast with time. Due to which an eye is created in the centre which is the low pressure centre into which the high pressure air flows from above, thus a cyclone is evolved. 

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