Hurricane Humberto, the eighth named storm to emerge this hurricane season, is currently swirling over waters north of the Caribbean. While forecasts predict Humberto won’t ever touch land, there is a possibility it could interact with another system, Imelda, which has developed nearby in the western Atlantic. 

That’s an unlikely outcome, said CBS News meteorologist Nikki Nolan. But if such a collision does occur, it could produce what’s called the Fujiwhara effect, a rare phenomenon in which two different storms merge and become entangled around a newly formed, common center. 

How the process plays out depends on the characteristics of the storms involved, according to the National Weather Service. The forecasting agency describes the Fujiwhara effect on its website as “an intense dance” between two tropical storms that can happen when they get close enough to each other on their respective tracks to reach a common point and either join together or spin around each other for a period of time before continuing along their individual paths.  

In the latter scenario, the storms involved must be comparably strong or large.

“Typically when one system is stronger than the other, the smaller and weaker system will get overrun by the larger, stronger one and completely eliminate it,” Nolan said. 

Similar systems “will dance around each other” before going their separate ways, she continued, adding: “Very rarely has a larger system absorbed a smaller one and become larger or stronger, but it is scientifically possible.”

“With the two tropical troubles currently north of the Caribbean, these two may interact under the Fujiwhara effect in the days ahead,” said Nolan. However, because the developing system “appears to be much weaker than Humberto and several miles away from it,” an interaction between the two — if one even takes place at all — may not result in a tangled gravitational “dance.” 

Humberto grew into a tropical storm Wednesday night while traveling over open waters in the central tropical Atlantic. It gained hurricane status early Friday morning and strengthened into a Category 5 on Saturday before weakening again.

It was forecast to pass west of Bermuda and remain a hurricane for more several days, the hurricane center said. 

The second system churning nearby strengthened on Sunday into Tropical Storm Imelda and then was upgraded to a hurricane on Tuesday. Imelda threatened to bring hurricane conditions to Bermuda by Wednesday evening.

Officials along the southeast U.S. coast from Florida to the Carolinas were watching Imelda closely, but its path skirted a direct hit on the mainland.

Nikki Nolan

contributed to this report.