Map credit: Tropical Tidbits
PHILADELPHIA - Have you ever heard of the Fujiwhara effect? This meteorological phenomenon is playing out with Hurricane Humberto and soon-to-be Tropical Storm Imelda.
Northeast and East Coast weather impacts
What we know:
Weather patterns in the northeast U.S. could see a shift due to the Fujiwhara effect.
When two powerful storms are near each other, one can get pulled into the other's spin. This interaction is seen on American, European and Canadian future radars, with Imelda moving toward Humberto.
If this pattern continues, the Carolinas might avoid significant flooding. The northeast, including New York, Philadelphia and Washington D.C., could experience sunnier skies and cooler temperatures by midweek.
Forecasters have been modeling this interaction for the last few days of September. It suggests a change from clouds to sunnier skies earlier in the workweek, with fall-like weather arriving soon after.
Map of Tropical Storm Humberto’s forecast cone and path from Sept. 25 to Sept. 30, 2025, showing it moving northwest from the Atlantic Ocean toward Bermuda. (NOAA)
Why you should care:
The potential Fujiwhara effect could bring unexpected weather changes to the northeast U.S., affecting daily life and travel plans.
Invest 94L is expected to become Tropical Storm Imelda this weekend.
What we don't know:
The exact path and impact of the storms remain uncertain. Residents should stay informed on the latest developments.
Atlantic Tropical Weather Outlook (NOAA)
The Source: Track the latest developments on the storms' paths with the National Hurricane Center.