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The Classification of Tropical Cyclones: Understanding the Different Categories

Typhoons: A Force of Nature

Tropical cyclones, commonly known as typhoons in the Northwest Pacific Ocean, are characterized by their powerful winds and destructive potential. These storms are classified into different categories based on their wind speeds, with each category representing a distinct level of danger.

Severe Tropical Storm (STS)

A Severe Tropical Storm (STS) is a tropical cyclone with maximum wind speeds ranging from 87 to 117 kilometers per hour (48 to 63 knots). These storms can cause significant damage, particularly to coastal areas and infrastructure.

Typhoon (TY)

A Typhoon is a tropical cyclone with maximum wind speeds of 118 kilometers per hour (64 knots) or higher. Typhoons are capable of causing widespread devastation, including flooding, landslides, and infrastructure damage. In the Northwest Pacific Ocean, typhoons are further classified into five categories based on their wind speeds:

• Category 1: 118 to 156 km/h
• Category 2: 157 to 184 km/h
• Category 3: 185 to 217 km/h
• Category 4: 218 to 249 km/h
• Category 5: 250 km/h or higher

Super Typhoon

A Super Typhoon is a tropical cyclone with maximum sustained winds of at least 150 miles per hour (241 kilometers per hour). These storms are the most powerful and destructive category of tropical cyclones and can cause catastrophic damage.

Tropical Cyclone Wind Signal (TCWS)

A Tropical Cyclone Wind Signal (TCWS) is a warning issued by weather authorities to alert residents of potential hazards associated with an approaching tropical cyclone. The TCWS indicates the maximum wind speeds that are expected to impact a particular area.

Hurricane

In the Atlantic Ocean and the Eastern Pacific Ocean, a tropical cyclone is classified as a hurricane if it has one-minute-average maximum sustained winds at 10 meters above the surface of at least 74 miles per hour (119 kilometers per hour).

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