In Summary
  • A tropical cyclone is a generic term used by meteorologists.

  • The World Meteorological Organisation, a UN body, maintains a list to name tropical cyclones around the world.

  • Hurricanes are categorised between 1 to 5 based on their wind speed.

In Tanzania, residents of Mtwara are scrambling to leave their homes as they escape the wrath of Cyclone Kenneth, which is set to make landfall tonight.

In North Carolina, efforts are underway to rebuild the infrastructure destroyed by Hurricanes Florence and Michael.

Similar efforts are ongoing in Saipan, more than six months after super typhoon Yutu battered the Western Pacific island.

So why do we call one a hurricane and the other a typhoon?

And while we're at it — what exactly is a cyclone?

ALL SAME

They are all the same thing: tropical storms.

But they are known by different names in different locations.

In the North Atlantic Ocean and Northeast Pacific, they are called hurricanes.

But if the same type of disturbance takes place in the Northwest Pacific Ocean, it is known as a typhoon.

And in the South Pacific and Indian Ocean, cyclone is the correct term.

GENERIC TERM

How bad do storms have to be?

A tropical cyclone is a generic term used by meteorologists.

It means a rotating, organised system of clouds and thunderstorms that originate over tropical or subtropical waters, according to the National Oceanic and Atmospheric Administration of the US.

"Once a tropical cyclone reaches maximum sustained winds of 74mph (119km/h) or higher, it is then classified as a hurricane, typhoon, or tropical cyclone, depending upon where the storm originates in the world."

WIND SPEED

Hurricanes are categorised between 1 to 5 based on their wind speed.

When do they occur?

In the Atlantic, it is hurricane season between June 1 and November 30.

More than 95 percent of tropical cyclone activity occurs during this period in this region.

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