Hurricane Experts on Whether Tropical Storm Nadine Will Form This Week

As another potential tropical storm brews in the Atlantic, hurricane experts have weighed in on whether it could become as powerful as Hurricanes Milton or Helene.

The low-pressure system that could become Tropical Storm Nadine is positioned in the Central Atlantic and could strengthen into a tropical cyclone—defined as any storm at tropical depression level or stronger—in the coming days.

The National Hurricane Center (NHC) says the storm has a 20 percent chance of reaching tropical cyclone strength in the next 48 hours and a 30 percent chance in the next seven days.

The NHC continued: "Showers and thunderstorms associated with a trough of low pressure located a few hundred miles east of the Leeward Islands remain disorganized. Some slow development is possible during the next few days as the disturbance moves quickly westward to west-northwestward around 20 mph, passing near the Virgin Islands and Puerto Rico on Friday, then near Hispaniola and the southeastern Bahamas on Saturday.

"Strong upper-level winds should end the chances of development by late in the weekend," the NHC added.

If this storm reaches tropical storm strength, it would be named Tropical Storm Nadine. However, according to the hurricane experts, it's not very likely to get to this strength.

Brian Tang, an associate professor of atmospheric science at New York's University at Albany, told Newsweek: "A forecaster at the National Hurricane Center takes into account multiple computer model forecasts, along with observations of the clouds and wind structure of the tropical disturbance, in order to assign probabilities of formation.

"A 20 to 30 percent chance of formation indicates small odds that the tropical disturbance will form into a tropical depression or storm over the next week," he said.

A storm is classified as a tropical depression when a low-pressure system develops over warm ocean waters, its wind circulation becomes organized and it has wind speeds of up to 38 mph. A tropical storm forms when the system strengthens further and wind speeds increase to between 39 and 73 mph. Above 74 mph, a storm is classified as a hurricane. A hurricane is classified as "major" when it reaches Category 3 or higher, with wind speeds above 110 mph.

To intensify into a tropical depression, and further into a tropical storm or even hurricane, a weather system has to encounter ideal conditions for the strengthening of a storm.

Annalisa Bracco, a professor of ocean and climate dynamics at the Georgia Institute of Technology, told Newsweek that very warm sea surface temperature (the engine in terms of energy for the storm to grow), low wind shear, and low surface salinity (or a well-stratified upper ocean in terms of its density) help storms to grow, concentrating the high temperatures near the surface.

Milton intensified very quickly during its journey across the Gulf of Mexico earlier this month, jumping in wind speed by 95 mph —from 80 to 175 mph—during a single 24-hour period, something only seen before with Hurricane Wilma in 2005 and Hurricane Felix in 2007.

Milton hit 180 mph at its most powerful point, making it the second Category 5 Atlantic hurricane this year so far, after Hurricane Beryl in July. Milton is considered the fifth most powerful Atlantic hurricane in recorded history by central pressure and is tied for the third-strongest hurricane in Atlantic history by wind speed.

The fact that the potential new tropical storm has stayed relatively the same strength for several days does not necessarily mean it cannot intensify into a more powerful storm.

Nicholas Grondin, an assistant professor of meteorology and physical geography at the University of Tampa, told Newsweek: "Hurricane Harvey in 2017 began to the east of Barbados and did not reach hurricane intensity until it was in the west-central Gulf of Mexico, where it rapidly intensified into a major hurricane before its landfall in Texas. Hurricane Laura in 2020 had a similar journey, where it began as a tropical storm just east of the Lesser Antilles and did not reach hurricane intensity until it was west of Cuba."

He continued: "Tropical cyclones will intensify if and when they encounter favorable environmental conditions, even if they had been a weaker system for a significant amount of time."

However, the weather conditions facing this particular potential storm are not ideal for its intensification, so this system may not be eventually crowned Tropical Storm Nadine.

"It is less common to have storms develop further east in the basin in mid/late October than for storms to form in the western Caribbean," Grondin said. "A limiting factor for this system's development will be increasing upper-level winds, which creates vertical wind shear, as it moves to the west. Vertical wind shear acts to limit development by disrupting the system's organization and disrupting heat and moisture transport within the system."

Current forecasts show the potential storm heading in the direction of Puerto Rico , the Dominican Republic and Haiti, although this may change as time goes by.

Xiangbo Feng, a tropical storm expert at the U.K.'s University of Reading, told Newsweek: "The path of storms is mostly controlled by the large-scale steering flow in the North Atlantic and partially by the storm itself, known as the Beta drift. The current numerical weather prediction models can simulate both factors.

"Forecasters generally follow the outputs of the models. But sometimes they also justify the path prediction using their subjective experience and based on the historic model performance," Feng said.

The storm therefore is not likely to travel anywhere near Florida, which is still reeling from the one-two punch of Milton and Helene in a single two-week period.

"Current forecasts do not have this tropical disturbance affecting Florida due to a high-pressure system over the eastern U.S. and cold front off the Florida coast that will keep the tropical disturbance offshore," Tang said. "At this time, I do not think residents of Florida need to be worried about this storm."

However, if the storm somehow strengthens into a more powerful tropical storm or even a hurricane and reroutes toward Florida, it could further exacerbate the immense damage caused by the previous two hurricanes.

"If this system were to develop and track near Florida, the impacts would be different," Grondin said. "The storm, based on what we know now, would be a substantially less intense storm, at most a strong tropical storm or Category 1 hurricane, and therefore would likely be a rain event.

"Its impacts from this angle would also be the most across South Florida, an area that received a record-breaking number of tornadoes from Milton, but not as much rainfall as further north. Gusty winds would also be a concern as well," Grondin said.