When two hurricanes combine or interact closely, it is called the Fujiwhara Effect. This phenomenon occurs when two tropical cyclones get close enough to each other, typically within about 350 to 860 miles depending on their size, and begin to rotate around a common center. They can either spiral around each other, potentially merge into one larger storm, or one storm may absorb the other if it is significantly stronger. The interaction can look like a dance around a shared midpoint before the storms either merge or continue on separate paths.