Tropical Storm Humberto, Invest 94L Eyed For Development: See Possible FL Impacts

With Tropical Storm Humberto forming in the Atlantic and Hurricane Gabrielle, once a Category 4 storm, heading toward western Europe, all eyes are on another potential storm threat to the eastern U.S. on Thursday.

While Humberto, which is centered near the Northern Leeward Islands, is facing ongoing wind shear, it’s not enough to weaken the system as it becomes better organized, the National Hurricane Center said.

The system is creating showers and thunderstorms and is expected to gradually strengthen during the next couple of days and intensify after the shear relaxes.

It could become a major hurricane by early next week as it moves southwest of Bermuda, NHC said.

Meanwhile, all eyes are on nearby Invest 94L, a tropical wave producing a large area of disorganized showers, thunderstorms, and gusty winds across parts of the Dominican Republic, and the Turks and Caicos Islands on Thursday.

• Related: ‘Rare’ Twin Storms To Threaten U.S. East Coast: See FL Timeline

An area of low pressure is expected to form along the wave Thursday night or early Friday as it moves near the southeast Bahama, NHC said.

The system has a 90 percent chance of strengthening over the next week. It’s expected to become a tropical depression as it passes the central and northwest Bahamas over the next couple of days, the agency said.

AccuWeather hurricane experts are forecasting a high risk of development are forecasting a high risk of development across the far southwestern Atlantic between Friday and Sunday.

The next named storm out of the Atlantic basin this year will be Imelda.

Those on the U.S. East Coast and in the Bahamas should monitor the brewing system which is expected to bring heavy rains and gusty winds to its path.

The system is forming parallel to Humberto and this twin-storm phenomenon, which is rare, is known as the Fujiwhara Effect, which happens “when two hurricanes spinning in the same direction pass close enough to each other, they begin an intense dance around their common center,” according to the National Weather Service. “If one hurricane is a lot stronger than the other, the smaller one will orbit it and eventually come crashing into its vortex to be absorbed.”

If the storms are similar in strength, they might merge as they gravitate towards each other or spin around each other before shooting off in different directions, NWS said. “In rare occasions, the effect is additive when the hurricanes come together, resulting in one larger storm instead of two smaller ones.”

The exact track and strength of Invest 94L as it strengthens by early next week will determine its location and potential impacts to the U.S.

There are two potential scenarios in play for the system.

“The first scenario sees the storm with lower wind intensity and being guided east toward a stronger Humberto (likely a major hurricane early next week). This may cause the storm to become completely enveloped and absorbed by Humberto, or dancing it around it,” AccuWeather forecasters said.

This would bring rough surf and a risk of rip currents along the East Coast.

In the second scenario, a stronger storm will track more directly toward the U.S. Southeast.

“This is because the storm would remain separate from Hurricane Humberto,” AccuWeather said of this more likely scenario.

This would bring more direct rain and wind to the U.S., most likely to North and South Carolina.

Denis Phillips, chief meteorologist for Tampa Bay 28, agrees that the system will likely head toward the Carolinas.

“Again, this isn't a threat for the Gulf,” he wrote in a Facebook post. “Speaking of which, we're still looking good..but trust me, the season is far from over for the Caribbean and Gulf. But for now, it's a big thumbs up!”

Matt Devitt with WINK Weather wrote in a Facebook post that the U.S. East Coast, including those in northeast Florida, could possibly feel impacts from this system between Monday and Wednesday.

“If impacts are felt across the Southeast, best chance right now would be the Carolinas into Georgia. Florida should still monitor, especially near Jacksonville,” he wrote.