How does a tropical depression become a tropical storm?

Answer 1

Cyclones are most often formed in the tropical areas, 5° and 20° north and south of the equator, owing to the Coriolis effect. Initially, a low pressure zone is formed in this area, which eventually forms a tropical wave of low pressure. This disturbance in the warm ocean waters, along with a light wind at the upper level, provides ideal weather condition for the formation of storms. With time, the intensity of the tropical wave may either increase or decrease. If the intensity increases, it goes on to become an organized area, characterized by heavy showers and thunderstorms. This organized area, marked by cyclonic winds blowing clockwise in northern hemisphere and anti-clockwise in Southern Hemisphere, is referred to as tropical depression. Equatorial areas, 5° north and south of the equator, do not facilitate formation of storms due to the lack of rotary motion of wind in this area.

Answer 2

A tropical depression strengthens into a tropical storm when maximum sustained winds reach 39 mph. This classification occurs when the storm organization and wind speeds increase, causing it to be named and further intensify.

Answer 3

A tropical depression becomes a tropical storm by gaining energy from warm ocean water. As this happens the winds increase. When they reach 39 mph the depression becomes a tropical storm.