What is the Fujiwhara Effect and how did it impact Tropical Storm Imelda?

The Fujiwhara Effect is an interaction between two tropical systems that causes them to dance around each other. In this case, the Fujiwhara Effect between Imelda and Hurricane Humberto steered Imelda away from the US coast, preventing a potentially devastating landfall.

How will the combination of Humberto, Imelda, and the high-pressure system affect the Southeast US?

The combined influence of these weather systems will lead to long-lasting rough surf, dangerous rip currents, and minor to moderate coastal flooding along the Southeast coast, from Florida to the Carolinas.

What is the impact on Bermuda?

Bermuda will face impacts from both Hurricane Humberto and Tropical Storm Imelda in close succession. The islands will first deal with Humberto's glancing blow, followed by a potential direct hit from Imelda as a hurricane later this week.

Home / Weather / Rare Fujiwhara Effect Steers Tropical Storm Imelda Away from US

Rare Fujiwhara Effect Steers Tropical Storm Imelda Away from US

29 Sep

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Summary

Hurricane Humberto and high pressure over Northeast steer Imelda away from US
Imelda's northward path blocked, avoiding potential major flooding in Carolinas and Georgia
Coastal areas still face long-lasting rough surf, dangerous rip currents, and flooding

Rare Fujiwhara Effect Steers Tropical Storm Imelda Away from US

As of September 29th, 2025, a rare meteorological phenomenon known as the Fujiwhara Effect is playing a crucial role in steering Tropical Storm Imelda away from the United States. The interaction between Imelda and the powerful Hurricane Humberto, tracking west of Bermuda, has caused the storm to take a sharp turn out to sea, avoiding a potentially devastating landfall.

Initially, Imelda was forecast to track inland over the Southeastern states, raising concerns about major flooding in the Carolinas and Georgia. In a worst-case scenario, it could have led to widespread inland and coastal flooding, comparable to the impacts of Hurricane Matthew or Nicole in 2016. However, a high-pressure system building over the Northeast has blocked Imelda's northward path, allowing Humberto to tug at the storm and steer it away from the U.S. coast.