Tropical cyclone
A tropical cyclone is a rapidly rotating low-pressure storm system that forms over warm tropical or subtropical ocean waters and is powered by heat and moisture from the sea.
A tropical cyclone is a rapidly rotating low-pressure storm system that forms over warm tropical or subtropical ocean waters and is powered by heat and moisture from the sea. It is the generic meteorological term for storms known regionally as hurricanes, typhoons, or cyclones. Tropical cyclones can produce destructive winds, heavy rain, storm surge, flooding, and other severe hazards.
Definition and structure
A tropical cyclone is a synoptic-scale storm with a closed surface wind circulation around a well-defined center. It is usually described by its low-pressure center, organized deep convection, eye, eyewall, and spiral rainbands.
Formation and energy source
Tropical cyclones form over warm ocean waters when atmospheric conditions are favourable. Their strength comes from heat and moisture drawn from the sea, which helps sustain organised thunderstorm activity.
Regional naming
The same weather system has different regional names. In common usage, storms are called hurricanes in the Atlantic and eastern North Pacific, typhoons in the western North Pacific, and cyclones in parts of the Indian Ocean and South Pacific.
Impacts and hazards
Tropical cyclones are among the most dangerous natural hazards. They can cause destructive winds, heavy rainfall, storm surge, flooding, coastal erosion, and secondary hazards such as tornadoes and lightning.
Key facts
- A tropical cyclone is a warm-core, non-frontal cyclone that develops over tropical or subtropical waters.
- It is maintained by heat energy extracted from warm ocean water.
- The same kind of storm is called a hurricane, typhoon, or cyclone depending on region.
- These storms can produce severe winds, torrential rain, storm surge, coastal flooding, lightning, and tornadoes.
Tropical cyclones mainly affect Canada indirectly, but their remnants can contribute to heavy rain, strong winds, storm surge, and flooding in Atlantic Canada and, more rarely, other regions.
Frequently asked questions
What is a tropical cyclone?
Are hurricanes and typhoons tropical cyclones?
What conditions are needed for tropical cyclones to form?
What parts does a tropical cyclone have?
What hazards do tropical cyclones bring?
References
- National Weather Service — https://www.weather.gov/mob/tropical_definitionsSupports: Definition of tropical cyclone as a warm-core, non-frontal synoptic-scale cyclone over tropical or subtropical waters.
- World Meteorological Organization — https://www.wmo.int/topics/tropical-cycloneSupports: Regional naming, general description, and hazards of tropical cyclones.
- Bureau of Meteorology — https://www.bom.gov.au/resources/learn-and-explore/tropical-cyclone-knowledge-centre/what-is-a-tropical-cycloneSupports: Formation over warm waters, sea-surface temperature threshold, and Australian regional definition.
- Met Office — https://www.metoffice.gov.uk/research/weather/tropical-cyclones/factsSupports: Generic term usage, regional names, and intensity thresholds for tropical depressions, storms, hurricanes, and typhoons.
- National Weather Service — https://www.weather.gov/media/lwx/skywarn/Tropical%20Cyclones.pdfSupports: Basic structure and regional naming conventions.
- NASA Earthdata — https://www.earthdata.nasa.gov/topics/human-dimensions/tropical-cyclonesSupports: WMO-based definition and low-pressure eye-centered structure.