Hurricane Helene path: How a Fujiwara effect could change storm

Hurricane Helene is barreling toward Florida with an expected landfall Thursday.

And while most of the forecast models have the storm striking the Florida Panhandle as a Category 3 hurricane, a rare atmospheric phenomenon called the Fujiwara effect could significantly alter the storm’s behavior.

But what is this effect, and how could it impact the current forecast for Hurricane Helene?

What is the Fujiwara effect?

Named after Japanese meteorologist Sakuhei Fujiwhara, who first described it in 1921, the Fujiwara effect occurs when two tropical cyclones come close enough to start rotating around each other, causing significant changes in storm intensity, track, and behavior.

The Fujiwara effect can impact storms in different ways.

The two storms can rotate around a central point between them, creating a larger storm footprint.

The storms can merge if they’re close enough and create a single massive storm.

In some cases, one storm can be pushed away from the other, spinning into a new path.

Why Hurricane Helene could trigger the Fujiwara effect?

In the case of Hurricane Helene, a nearby, low-pressure system in the south could interact with Helene as it moves toward Florida, possibly triggering a Fujiwara effect.

Helene is expected to make landfall as large storm, carrying wind and rain bands extending far from its center.

If it does interact with another storm on its way in, Helene could veer off its expected path, carry even more rain than forecasted or push damaging winds over a larger area.

Was Superstorm Sandy a Fujiwara effect?

Hurricane Sandy in 2012 interacted with another storm, ramping up its intensity and causing it to hang a sharp left turn toward the Northeast.

But, while a superstorm, Sandy was not a classic Fujiwara effect because the two storms did not rotate around each other.

This article originally appeared on NorthJersey.com: Hurricane Helene path: How a Fujiwara effect could change storm