A typhoon is a tropical cyclone that occurs in the western Pacific Ocean and South China Sea. It is usually characterized by strong winds, heavy rain, and large waves. Typhoons typically occur between May and November and often cause damage to coastal areas.
The word “typhoon” is derived from the Greek word for whirlwind, τυφών (tuphōn). The first recorded use of the word in English was in 1588, during the Spanish Armada. Early sailors called these storms willy-willies or simply hurricanes.
Typhoons are caused by low-pressure systems that form over warm ocean waters. These systems can develop into tropical depressions, which are areas of low pressure with thunderstorms and winds of at least 17 mph (28 km/h). If a tropical depression continues to grow stronger and reaches sustained winds of 39 mph (63 km/h), it becomes a tropical storm. Once wind speeds reach 74 mph (119 km/h), it officially becomes a typhoon.
Typhoons typically move westward across the Pacific Ocean and generally weaken as they approach land due to interaction with cooler air and landmasses. When they make landfall, they can bring strong winds, heavy rains, flooding, and landslides. In recent years, some typhoons have also been responsible for causing tornadoes.
While typhoons can be dangerous, most people living in coastal areas have learned how to prepare for them and take precautions to minimize damage. For example, many homes are built with Typhoon shutters or glass windows that can withstand high winds. People also typically stock up on food and supplies before a typhoon hits so that they can be self-sufficient for several days if necessary.
There are several different warning levels for typhoons issued by various weather agencies around the world:
* A Tropical Cyclone Formation Alert is issued when conditions are favorable for the development of a tropical cyclone within the next 24 hours * A Tropical Cyclone Watch is issued when a Tropical Cyclone Formation Alert has been issued AND there is potential for tropical cyclone formation within 48 hours * A Tropical Cyclone Warning is issued when a Tropical Cyclone Watch has been upgraded to a warning AND there is potential for tropical cyclone formation within 36 hours