Tropical cyclogenesis

A global map showing where tropical cyclones form from 1985 to 2005.

Tropical cyclogenesis is a meteorological word used to describe tropical cyclone formation, and its strengthening over the atmosphere.^[1] Tropical cyclogenesis happens when the development of a warm-core cyclone, is associated with a lot of convection in a favorable atmospheric environment. Usually, about 86 tropical cyclones of tropical storm strength form worldwide every year, with 47 reaching hurricane/typhoon strength, and 20 becoming strong tropical cyclones (at least Category 3 intensity on the Saffir-Simpson Hurricane Scale).^[2]

Tropical Cyclogenesis Media

Depth of 26 °C isotherm on October 1, 2006
Waves in the trade winds in the Atlantic Ocean—areas of converging winds that move slowly along the same track as the prevailing wind—create instabilities in the atmosphere that may lead to the formation of hurricanes.
Schematic representation of flow around a low-pressure area (in this case, Hurricane Isabel) in the Northern hemisphere. The pressure gradient force is represented by blue arrows, the Coriolis acceleration (always perpendicular to the velocity) by red arrows
Tropical Storm Paulette in 2020, with its low-level centre partially exposed due to strong windshear.
Peaks of activity worldwide
Hurricane Pablo formed in the extreme northeastern Atlantic during the 2019 season.
Loop of sea surface temperature (SST) anomalies in the Tropical Pacific
ENSO effects on hurricanes distribution.
5-day running mean of MJO. Note how it moves eastward with time.