The Fujiwhara effect is a phenomenon that occurs when two nearby cyclonic vortices move around each other and close the distance between the circulations of their corresponding low-pressure areas.
When cyclones are in proximity of one another, their centres will circle each other cyclonically (counter-clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere) about a point between the two systems due to their cyclonic wind circulations.
The two vortices will be attracted to each other, and eventually spiral into the center point and merge.
When the two vortices are of unequal size, the larger vortex will tend to dominate the interaction, and the smaller vortex will circle around it.
Recently two tropical storms, formed in the western Atlantic Ocean at nearly the same time, are likely to impact the Gulf of Mexico, sparking concerns of the rare Fujiwhara effect that occurs when two hurricanes combine to form a mega hurricane.
Marco is the 13th named storm of the Atlantic hurricane season which runs from June to November.
Tropical storm Laura is the 12th named storm of the season and is currently hovering over the Caribbean.
Their simultaneous formation in the western Atlantic Ocean created a Fujiwhara effect scare.