Have you heard of a Depression? No, not the emotion. The weather condition.
Well, if you know what a cyclone is then Depression is the beginning stage of a tropical cyclone.
This is how it occurs. When a fast-moving area of cool air meets a region of warmer air above 21ºC it causes the warm air to rise up and the cool air to go under the warm air. This forms clouds about 10 feet in the air. The air cools down and causes rain. As a result some energy is released and moves around slowly, looking for more warmer air and as the warmer air gets sucked in, it causes low pressure and thus, the Depression is formed.
A Depression is the first stage of a cyclone and, it is somewhere between 39mph-79mph wind speed. Depressions can be very unsafe as they can cause rip currents which are narrow currents and dangerous waves which are deadly to people in the water or close to water.
They also result in heavy rain.