Although dynamics of Tropical Cyclones is extremely complex, yet meteorologists have identified certain climatological conditions that favor its development. The climatic conditions necessary for the formation of Tropical Cyclones are:
High evaporation depends on warm waters. Thus Tropical Cyclones only develop over warm waters. Water temperature above 27 ° C for a considerable depth is thus required. Cyclones do not form at higher latitudes, since the water is not warm enough for the development.
- Cyclone formation also depends on Coriolis Force that must be strong enough to initiate the cyclone’s rotation. It should prevent filling of the central low pressure. The absence of Corioils Force near equator limits the formation of tropical cyclone between 0°- 7° latitudes.
- Pre-existing low-pressure system or a slight weather disturbance.
When the conditions are conducive, these low-pressure systems transform to tropical depressions followed by tropical storms and finally tropical cyclone.
- Upper air circulation should support the thunderstorm formation.
- Low vertical wind shear to support the structural of tropical cyclone. High wind shear can break the cyclone structure.
Once formed the tropical cyclones can sustain themselves i.e. they are self-maintaining. The wind diverges at the top of the cyclone. The diversion draws more air upwards that results in a low pressure at the surface leading to further uplift of air. This continuous process of uplift, condensation, release of latent heat keeps the cyclone alive. On landfall, the source of energy is cut off and hence cyclone weakens and finally dissipates.
Hurricane Dates and Names