Typhoon and Tropical Cyclone

What is a typhoon?

A typhoon is a violent cyclone that occurs in the northwest Pacific Ocean. Typhoons feature heavy rains and winds that maintain speeds equal to or greater than 74 miles (119 kilometers) per hour. Similar storms that occur in other parts of the world are called tropical cyclones or hurricanes. The word typhoon comes from the Chinese term tai-fung, meaning great wind.

Typhoons occur most frequently in the late summer. They form over warm seas between about 5 and 20 degrees of latitude from the equator. They tend to move west, northwest, and eventually northeast at speeds of 10 to 20 miles (16 to 32 kilometers) per hour. Inside a typhoon, strong winds blow in a counterclockwise direction around an area of low pressure at the storm’s center, which is called the eye. The eye usually measures about 10 to 40 miles (16 to 64 kilometers) in diameter. The strongest winds blow inside the eyewall, a ring of clouds that surrounds the eye. These winds often reach speeds of more than 110 miles (180 kilometers) per hour. The heavy rains and strong winds of a typhoon can cause great loss of life and billions of dollars in property damage. As a typhoon approaches lands, its winds produce a rush of seawater called a storm surge that can devastate coastal areas.

Ref(http://www.worldbook.com/wb/Students?content_spotlight/hurricanes/cyclones_typhoon)

What is a tropical storm or tropical cyclone?

A tropical cyclone is a relatively small, intensely developed low pressure cell that usually occur over warm oceans. Its diameter can range between 200 and 2 000 km. It is characterized by a warm centre, very steep pressure gradients and strong cyclonic (clockwise in the southern hemisphere) winds near the Earth’s surface.

Tropical cyclones with a maximum wind speed of less than 60 km/h are called tropical depressions; when the maximum wind speed ranges between 60 and 110 km/h, they are tropical storms, and when the maximum wind speed exceeds 110 km/h, they are called tropical cyclones. (In the North Atlantic and eastern North Pacific regions it is called “ hurricanes” , in the western North Pacific “ typhoons” .)

Ref (http://www.weathersa.co.za/References/Cyclones.jsp)