After weeks of calm, a tropical storm may form in the Atlantic this week
After 18 days without a storm in the Atlantic, a storm is likely to form later this week.
The National Hurricane Center estimates an 80% chance a system will develop in the next week. A clump of downpours and thunderstorms was present midway between the Lesser Antilles and Africa in the central tropical Atlantic and is poised to organize in the days ahead.
By the weekend, it could be a named storm – the next name is Gabrielle.
Weather models suggest it could become a powerhouse hurricane as it remains mostly out to sea. While at this point, it appears the storm could pass north of the Leeward Islands and curve northwards over the open Atlantic, it could pose an eventual threat to Bermuda.
The Atlantic has been silent since the dissipation of Fernand on Aug. 27. Forecasters initially called for an extra-active hurricane season, and now many are wondering whether the Atlantic will reach even average activity. Tropical activity is 47% below average. In fact, there’s been only one hurricane so far – Erin.
Erin became a Category 5 monster northeast of Puerto Rico on Aug. 16, but it never hit land. The other five systems of 2025 were all tropical storms.
There’s a chance that the Gulf of Mexico and the Caribbean could become areas to watch in a couple of weeks, but as of now, that’s a low-end potential.
What to know about the system
On Monday morning, the disturbance that forecasters are monitoring was over the central tropical Atlantic moving west-northwest at 10 to 15 mph. It was blossoming with robust thunderstorm activity but had yet to consolidate a pocket of spin to stretch into a cohesive central vortex. Until a low-level center and closed circulation form, the thunderstorm cluster will be slow to strengthen.
The National Hurricane Center anticipates that will happen sometime later this week. That will make the system a tropical depression, or the precursor to a tropical storm.
It should begin to steadily strengthen, and it could form into a Category 2 or stronger hurricane as it passes north of the Lesser Antilles over the weekend. By early next week, it could be approaching Bermuda as it curves northward on the back side of clockwise-spinning high pressure anchored over the central Atlantic.
Why has the Atlantic been so calm?
The Atlantic has been relatively silent for weeks. Last week, there was a tropical wave – Invest 91L – that forecasters pegged with a 90% chance of development. But even that fell apart. The ocean just can’t seem to squeak out a storm.
“There was a lot of dry air around,” Phil Klotzbach, a hurricane researcher at Colorado State University, said in an interview. “If the dry air gets in, it can really just kill it. And, you know, [the disturbance] didn’t get far enough along.”
Even when forecasters and computer models have a good idea of the overall state of the atmosphere, subtleties – such as when exactly a system’s spin will tighten up and make it a storm – are poorly understood.
What comes next?
There are signs that, around next week, a zone of ascent will overspread the Atlantic. That will encourage more thunderstorm and tropical wave development , bolstering the potential for hurricane formation.
It’s almost the time of year when the Atlantic’s MDR, or Main Development Region, begins to simmer down. That’s the zone between the eastern Caribbean and western Africa. But at the same time, that’s when our focus usually shifts to the western Caribbean and the gulf.
That’s because of something called the Central American Gyre. As the seasons change, a broad, large-scale zone of weak spin and unsettled weather typically forms over Central America. It brings thunderstorms and squally weather, but occasionally that vorticity, or spin, can tighten and form a sporadic storm. Sometimes that happens over the eastern Pacific, and other times over the western Caribbean or the Bay of Campeche.
Milton last year formed out of the Central American Gyre, for example. So did Hurricane Michael in 2018. And while there’s nothing imminent on the horizon, the Climate Prediction Center has highlighted that area as a place to keep tabs on as the Central American Gyre begins to materialize in the coming weeks.