Ladies and gentlemen, we may get to witness an extremely unique weather phenomena coming into early next week. There has been a lot of talk about something called the “Fujiwhara Effect” and this is becoming more of a real scenario which makes forecasting very difficult. We already have Humberto which formed yesterday in areas north and east of the Lesser Antilles which is expected to become a major hurricane towards the weekend. Another tropical wave near Hispaniola is expected to develop into Imelda and will become in close enough proximity to Humberto to do a bit of a waltz we can say.
First off what is the Fujiwhara Effect? The Fujiwhara effect describes the rotational interaction of two vortices, such as tropical cyclones, where they orbit a common center and can either merge into one larger storm, cause one to be absorbed, or break apart and move away from each other. The effect, named after Japanese meteorologist Sakuhei Fujiwhara, is more common in the Pacific Ocean, where tropical cyclones are more numerous.
This is exactly what we have going on here with potentially two tropical cyclones is close enough proximity to start doing some very strange movements as they share a similar fulcrum point between each other. Humberto should stay off our coast but Imelda is the one to watch as this becomes a threat towards the Southeast US coastal toward the Mid-Atlantic coasts. To throw a bigger wrench into things, we have a strong surface high moving in across the Great Lakes and New England with a retrograding upper level low in the Midwest. So many steering currents to bring what would be Imelda towards the US Coastlines. And could stall Imelda in place with a tremendous rainfall threat.
We really need to see if Imelda can form a center of circulation to get a better handle on where it would go and the impacts with the Fujiwhara. This is going to be a fairly impactful and intriguing setup overall. The meteorology behind this is truly astonishing. Regardless, residents along the Eastern Seaboard need to relate alert as we head into the weekend.