Fujiwhara Effect

The Fujiwhara Effect, also known as the Fujiwara interaction, is a meteorological phenomenon that occurs when two nearby cyclonic vortices move around each other and begin to rotate about a common midpoint. This effect is named after Dr. Sakuhei Fujiwhara, a Japanese meteorologist who described it in 1921.

The interaction often results in one of the storms absorbing the other, changing their trajectories and potentially altering their intensity. The Fujiwhara Effect is most commonly observed with tropical cyclones (such as hurricanes and typhoons) in the Atlantic and Pacific Oceans, but it can also involve other types of cyclones. It usually occurs when the cyclones are within 1,400 kilometers (870 miles) of each other.